National Geographic Magazine/Volume 1/Number 1/The Survey of the Coast

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THE SURVEY OF THE COAST.

By Herbert G. Ogden.

At the inception of the Coast and Geodetic Survey in the early years of the century, so little was known of the dangers attending navigation along our extensive seaboard, that those who engaged in commercial enterprises were constrained to rely upon local knowledge and the reports of the hardy navigators who might carry their ventures to success. The charts available were by no means a sure reliance, and it has since been shown, contained many serious errors. The great headlands and outlying shoals that present the greatest obstacles to the safety of coast-wise navigation, had not been carefully surveyed, and their relative positions to one another were only approximately determined.

The capacities of the harbors had not been ascertained, many were unknown; and even at the great port of New York, the Gedney or Main channel, was not developed until after the permanent establishment of the Survey in 1832, and the thorough exploration of the entrance was undertaken. A list of the sunken dangers and new channels that have been discovered during the progress of the work would fill pages. It is true such developments were to be expected in making a precise survey of the comparatively uncharted coast; but they, nevertheless, clearly point to the necessity of the work. We may also assume that the men who were controlling the destinies of the republic, realized that a knowledge of the coast was essential if they would succeed in building up a commerce, without which it was believed the prosperity of the people could not be assured. The deep draught vessels of the present day could not have traded along our shores on any margin of safety with the little that was known, and it is largely due to the perfect charting of the coast, that commercial enterprise has found it practicable to build the larger vessels of modern type to meet the increasing demands of trade.

The survey proposed was also required in providing for the public defence; as it is a self-evident proposition, that if we would protect a harbor from a hostile fleet, we must know not only the channels by which the fleet might enter, but their relations to each other and the points of vantage that should be utilized in obstructing them; and in modern warfare to know these things only approximately will not suffice, for precision is practiced now in the art of war, as well as in the arts of peace.

The lack of charts of our extensive Coast line, or indeed, of any practical information that could be utilized in a systematic defence against foreign aggression, was only one of the many perplexities that surrounded our forefathers in building the nation. By their valor they had wrested a jewel from the British Crown, and had inaugurated a system of government by the people, which on their sacred honors they had sworn to defend. But not a generation had passed away when they saw new dangers, and were forced to contemplate again taking up arms in defence of their rights. The land was theirs, even far towards the setting sun, pioneers had explored it, and they knew whence might come a hostile foe. But of the waters from far away to the eastward, that flowed on until they washed every shore and filled the great Bays, even to the heart of the Republic, they knew little, save that over that almost immeasurable expanse might come the fleet of destroyers to penetrate they knew not where, and inflict incalculable damage months ere the dreary tales might be told. It must be remembered there were no telegraphs, no railroads, no steamboats, in those days, and time taken by the forelock was time gained. The speed of man could not be overtaken as we see it to-day in the wondrous inventions of the last generations. Each community was dependent upon itself, alone, in time of danger, to ward off the blow or yield to a more powerful foe; assistance could hardly be obtained in months and perhaps not then. It was not possible for any man to study or to learn the points of danger, and prepare a system of defence.

President Jefferson in his far-seeing statesmanship, threatened with war, realized the danger. A survey of the coast he believed essential to the national defence, and to the prosperity of the nation in time of peace. Had his wise counsels prevailed and the survey been prosecuted with vigor, instead of being almost immediately suspended for a quarter of a century, there can be no question but that it would have saved the people millions of dollars in expenditures and put other untold millions into their coffers, through the impetus it would have given to commerce years before commerce actually had a name in many that are now thriving seaport towns.

But it is not to be supposed the commercial importance of a knowledge of the coast and harbors was underrated because the Survey was not prosecuted. The people were poor, the task would be expensive and laborious. The appliances for the work were not in the possession of the Government, and above all, war came came sooner than was anticipated and the energies of the people were taxed to the utmost in combat with their powerful foe; and when peace came again, there was the inevitable commercial depression that follows a resort to arms. The men of the day fully realized how illy they were prepared to invite commerce to our shores, or incite our own people to more extensive trade. There was nothing to adequately represent those magnificent harbors that have since become famous the world over; nor of that long line of coast with its treacherous shoals, whereby those seeking new ventures might judge of the dangers to be encountered. The absolute ignorance that existed was aptly described in the Albany Argus in 1832, when the propriety of reviving the act of 1807 was under discussion, as follows:

"It had been discovered by an American statesman that parent countries always keep the commercial knowledge of their colonies as a leading-string in their own hands, and that as practical navigators, American seamen knew less of their own shores than the country and its allies from whose subjection we had recently delivered ourselves by force of arms. In large vessels, three nations, the Dutch, the French, and the English, approached our harbors with less risk than those bearing our own flag; at the same time that in small and more manageable vessels, we had long been known as a match for the strongest. The president, Jefferson, saw the defect and the manner in which it must be remedied. We were at that time on the brink of war, about whose justice some of our politicians differed in opinion and it was, of course, more necessary to pray for a fortunate result than to preach the causes which had occasioned the quarrel. To have procured for the nation (even had it been practicable so to do) the old charts from the Dutch, French, and English governments, would have only been to put our knowledge on a par with theirs, while to execute more recent and accurate surveys, was advancing the new country above the old. With the clear and bold perception, which always distinguishes men of genius when they are entrusted in times of danger with the destinies of a nation, the president recommended a survey of the whole coast with all the aid of the more recent discoveries of science."

The proposed survey was strongly advocated by President Jefferson, and the Secretary of the Treasury, Mr. Gallatin, and in February, 1807, Congress passed the first act providing for the work. Thirteen separate plans, or schemes, were submitted for consideration; among the number was one by Professor F. R. Hassler, which was finally adopted, and Professor Hassler was appointed the first superintendent. It is not necessary to dwell, in detail, upon the varying fortunes of the survey during the three-quarters of a century that have passed since the original act authorizing it. The first thirty years of experiment, before it was finally established as a bureau of the Treasury Department, show only too clearly the ignorance and prejudice against which the supporters—we may say founders—of the survey had to contend. But they had only the experience of all men who attempt the inauguration of new things of which it cannot be shown that they will return a cash profit at the end of six months. To the opponents of the measure cash could not be seen at all, and the profit, whatever it should be, was only an intangible kind of benefit to be realized in the future by additional security to their property and commerce; but, in reality, as has since been appreciated, the direct saving of many millions of dollars annually.

The war of 1812 interrupted Professor Hassler's labors and it was not until 1817 that he actually commenced work; but he was stopped the next year by a limitation of the law requiring the work to be performed by the Military Departments. In 1832 Congress passed a special act reviving the law of 1807 and Professor Hassler was again appointed Superintendent. A further interruption occurred in 1834 by the transfer of the bureau to the Navy Department, but this was of short duration, as it was re-transferred to the Treasury Department in 1836, where it has since remained. Professor Hassler continued as Superintendent until his death in November, 1843. He was succeeded by Professor A. D. Bache, who was fortunate in assuming the charge under much more favorable auspices than had prevailed under his predecessor.

By the appropriation bill passed in March, 1843, the President was directed to appoint a Commission to reorganize the Bureau and prescribe methods for its future conduct. The plan recommended by the Commission was substantially that which had been followed by Professor Hassler. It was approved by the President a few months before Professor Bache assumed the superintendency and has since been the law for the execution of the work. To have a law specifying in detail the methods that should be employed in prosecuting the surveys, that had been drawn by a special commission of experts and approved by the administration, relieved the Superintendent of much of the responsibility that had been borne by Professor Hassler, although it did not put an end to the carpings of the critics, or their advocacy of the less expensive "nautical surveys."

The reorganization provided for the employment of civilians and officers of the Army and Navy to serve directly under instructions from the Superintendent; thus securing for the service the opportunity to procure the best talent from either civil or military life. The civil element, it was assumed, would form a body of experts for the prosecution of those branches of the work not properly falling in the direct line of the military, and experience has demonstrated that while the results anticipated have been fully realized, the organization has not only proved effective but conducive to the advancement of the survey in many ways. The Civil War was a serious interruption, but alone, proved the wisdom of the civil organization of the Bureau. On the outbreak of hostilities the military element was necessarily withdrawn for duty with the Army and Navy; and it was not until ten years after the close of the war that officers of the Navy were again available, while officers of the Army, through the exigencies of the Military service, have not returned at all. The organization was preserved through these fifteen years by the permanent civil nucleus, and the work suffered no deterioration, but steadily advanced, notwithstanding that the larger number of the civilians were constantly employed during the four years of the war with the Armies and Navy, in different capacities on the staffs of commanding officers; and that the urgent necessities of the government devolved additional labor, and temporarily, a new class of work upon the office force in compiling, draughting and publishing maps of the interior for the use of the Armies in the field. And when finally, our Armies were disbanded and our fleets reduced to a peace basis, and officers of the Navy resumed the execution of the Hydrographic work, it was but to step into the duties of their predecessors; they had, too, the additional advantage of the fifteen years' experience of the purely civil administration of the Survey, during which time the trained surveyors of the land had become equally expert as surveyors of the water, and had added not a little to the improvement of Hydrographic methods. The History of the Survey shows a steady advance in methods of work from its foundation to the present day. But so equally has the march of improvement been due to the zeal and untiring efforts of the civilians and officers of the Army and Navy alike, that any distinction would be invidious.

The plan of reorganization of 1843 provided for a detailed survey of precision. It was to be based on an exact triangulation that would insure positive results, that the location of a danger or the development of a new channel, should be beyond doubt; and that the survey, when completed, should fit together as one continuous line, in which the distance and direction of any object on the map from any other object should be true, whether the objects were in hailing distance of one another, or at the extremes of our boundaries. So well was the scheme conceived, so perfect has it proved in operation, that it is substantially the guide for the closing labors of the great work, notwithstanding the many improvements that experience has wrought in the details.

Those engaged upon the Survey have been quick to profit by experience, and the master mind of Professor Bache, the second Superintendent, was not slow to adopt that which promised increased economy, rapidity or improvement. He drew from all sources, Science contributed her quota and the great inventive genius of the American people played an equal share in producing the final results.

The researches that were necessary to obtain the information required by law "for completing an accurate chart of every part of the coasts," have produced results of great economic and scientific value to the whole people, aside from their bearing on the interests of commerce and navigation; and which will contribute to the welfare of mankind long years after those who labored for them have passed away. A brief reference to a few of the many instances that might be cited to illustrate this perpetual influence to benefit our fellow men, may not be without interest to some of you present.

The application of the method of determining latitude by the measurement of small zenith distances, introduced by Captain Andrew Talcott of the Engineer Corps, U. S. A., while serving as an Assistant on the Survey, developed such radical errors in the star places given in the catalogues, that it led to an almost immediate call for better places, and arrangements were made with the observatories of the country to obtain the necessary observations, the Survey to pay for the labor involved. Stimulated by the knowledge that better work was required to meet the new demand, observatories deficient in instruments procured new ones, and soon furnished more accurate star places. Continued observation has added still further improvement until to-day we have catalogues that furnish the highest degree of precision. Professor Chauvenet defines "Talcott's method" as "one of the most valuable improvements in practical astronomy of recent years, surpassing all previous known methods (not excepting that of Bessel by prime vertical transits) both in simplicity and accuracy." But the advantages of the method have been found to be of a practical nature also; as it is productive of large economy in time and labor and has reduced the cost of the Survey many thousands of dollars.

The introduction of the Electric Telegraph was utilized by the Survey immediately on the practical accomplishment of the first line built, as a ready and improved means for determining longitude. Indeed, before Professor Morse had demonstrated to the world the truthfulness of his theories and experiments, the bare possibility of their success, and availability in the instant transmission of time, had been discussed on the Coast Survey, and the method to be first employed fully considered. But as in the application of all things under new conditions, experience is the teacher, and improvements were frequently made, until finally the invention and perfection of the "chronograph" has brought the method to a degree of precision that little more can be looked for. This method of determining longitude, introduced, fostered and perfected on the Coast Survey, has been more far reaching than geographical boundaries. All civilized nations have adopted it as the "American Method," and by the greater accuracy and reliability of the results the whole world has profited. The saving that has accrued by the more perfect determination of longitudes and the consequent increased safety to commerce, may be counted by millions every year; until one stands aghast in contemplation of the immensity of the sum, and fears to reckon it, even approximately, much less to prophecy what it may reach in the future. The system is but a natural sequence of the development of the telegraph, but emphasizes in a marked degree the spirit of progress that has ever been the active principle and guide in the conduct of the work, and advanced its methods to a state of perfection that has called forth the admiration of the scientific world.

The determination of the magnetic elements has been a subject of investigation from the early days of the survey; the knowledge sought was essential to the navigator, and in recent years, especially, has proved to be of the greatest practical value on shore. Limited by small appropriations the research was at first slow. But a trust fund left by Professor Bache, who always evinced the warmest interest in this particular investigation, added largely to the rapidity with which observations could be obtained, until now we have magnetic maps of the United States of such reasonable precision that they are authoritative, and are in almost daily demand. The results are more far reaching than their mere tabulation for the current year, as laws have been determined by which the declination in a locality can be ascertained for any year in the past.

There are but few places where the needle remains stationary, or points in the same direction, for any great length of time; it even changes daily and during the hours of a day; but the aggregate for a year will rarely exceed three or four minutes of arc. If we reflect then, upon the great use made of the compass in the settlement of the continent, and the proverbial neglect of the country surveyor of those days to record the local variation, or declination, with his work, we may see a little of the utility and practical purposes to which the results are constantly being applied. Property so little thought of a hundred years ago that a few acres more or less, lost or acquired, in its transfer defined by compass surveys, may suddenly assume a value in these days of progress that every square foot is worth dollars. When a dispute arises, deeds are examined, lost or obliterated marks are diligently sought for, perhaps one is found, surveyors are employed to run out the lines but only make the confusion worse. Instead of a few rods that were in doubt according to the best information, the surveyor's line makes it acres, and litigation looms up to eat the profits of the sudden rise, and there seems even then no satisfactory solution of the vexing problem. How valuable then must be the fact, that it is possible to compute the variation for years back, to the time the original survey was made, and furnish the deflection that will re-run the lines so clearly as to render the descriptions in the deed intelligible. This is but a single instance of the practical application of the knowledge gained; and if its general usefulness may be judged by the numerous inquiries made of the Bureau, it is not unreasonable to assume that time will bear increasing testimony of its great economic value from those who traverse the land, as well as those who sail on the waters.

The study of the recurrence of the tides along our extensive Coast lines, and determination of laws that would satisfy the great variance in the different periods, was a problem of no little magnitude but the greatest possible importance to our commerce. Much of the traffic along the coasts literally moves with the tides, and the cost of transportation is enhanced or diminished as the tide retards or advances it. Hundreds of dollars of expense may be incurred on a single cargo that must enter on the high water, but through imperfect knowledge of the master of the ship, is forced after sighting his port, to wait for the next tide, perhaps over night, and is driven to sea by a sudden storm and the voyage made several days longer. Such mishaps are not infrequent, and even at the great port of New York certain classes of vessels must "wait for the tide." The investigation of this complex subject has resulted in the acquirement of a knowledge that enables the prediction of the time of high and low water, and the height of the tidal wave, years in advance; and the mariner may now carry with him the tables published on the subject wherever he goes, and be independant of the doubtful communications he may otherwise receive from the shore. How many lives, how many dollars, have been saved by the knowledge gained?

But the investigation of the Tidal phenomena is of great scientific importance also; and a practical assistance in the great problems involved in the preservation and improvement of our harbors, but in this connection it probably falls more properly under the head of that greater study of the currents and their effects in the erosion, and building of the shores; the movement of the sands and formation of shoals and channels; termed "Physical Hydrography." Our commerce depends largely on this study for its perpetuation, for without harbors commerce must cease; and without harbors that will admit vessels of the largest class it must deteriorate. If commerce finds increased profits in large vessels it demands increased facilities, and the bars to the harbors with but six or eight feet of water on them a few years ago, must have ten, perhaps fifteen feet now, or the people must suffer their trade to pass to some more fortunate or energetic neighbor. This may be a hardship; but the demands of trade are inexorable, the profits must be reasonably assured, and those who would have the trade must comply with the requirements. Thus we see the striving for harbor improvements; the weakest making the greatest outcry that they shall not be left in the race. And the improvements must come in the end, or at least be attempted, for it is as much a law of commerce not to be hampered by small freights, as it is the law of nature that water flows down hill.

The outcry for "improvements" never grows weaker; it is the expression of a sincere conviction that the life of the community and the welfare of the "back country" depend upon its success for prosperity; it will not admit a rebuff and knows no such word as failure. Alleged authorities are consulted, a scheme of improvement is proposed and Congress is asked to vote the money, and finally the improvements are attempted. To be successful, the plan must conform to known general laws and the peculiarities of local conditions, many of which are only ascertainable by comparison of surveys at different periods. Theories advanced on data collected by one survey, may be strengthened or disproved by the facts ascertained in a subsequent survey; and it is only when the plan proposed meets the general laws and the local conditions at the same time, that it holds out promise of success. The study of the questions involved has been greatly aided by the work of the Coast Survey in improvements already attempted, and will be of greater assistance in the future. A positive knowledge of what the local conditions were when a harbor was at its greatest capacity, is of the greatest help in indicating the improvements necessary to restore it, after deterioration, or to maintain it in the full measure of its usefulness. Reliable charts do this, but they tell only half the story. A cause must be found for the effects that have been produced, and the remedy suggested must overcome that cause or control it, that it may work good instead of evil. In Physical Hydrography we learn the forces that nature has given us in the tides, the currents and the winds, and divert them from powers of destruction, as man in his ignorance may have led them, or in their warfare with one another they may have led themselves; and bring their mighty influence to protect, improve or maintain that which we originally had. Many harbors have suffered incalculable injury through the recklessness of these who live upon them, and whose daily bread is dependent upon their preservation; until the evil has become so great that commercial cities have now "Harbor Commissions," whose special function is the preservation and improvement of the harbors. The original surveys made by Coast Survey are the foundations on which they very generally must build, while re-surveys point out to them the obstacles that must be overcome. And thus it will ever be; and future generations endeavoring to meet the demands of commerce for increased facilities, will have still greater cause for thankfulness, that the wise men who inaugurated the work of the Coast Survey, determined that it should be executed with every improvement that science could devise; and that the able men who conducted it, did not yield to the clamor for quick returns and cheap results, of only momentary value. They will realize by the benefits they will derive from it, as do those now living who have watched its progress and development, that the best is the cheapest as it will be useful through all time.

In 1871 Congress authorized the execution of a Geodetic triangulation across the continent to connect the great primary triangulations along the Atlantic and Pacific coasts, and provided that the triangulation should determine positions in those States that made requisite provision for topographical and geological surveys of their own territories. Each year since then, a small sum has been expended on these works with gratifying results to the States that have availed themselves of the assistance. But it was not until 1878 that Congress designated the Bureau as the "Coast and Geodetic Survey," the official title it bears at this time. Many comments have been passed upon the action of Congress in extending the field of the survey to the interior in the establishment of a "Geodetic Survey," which has been looked upon as a purely scientific research for which the people had no immediate use, and could well afford to wait. But if the tree can be judged by its fruit, there will be no lack of testimony to the economic value of the Geodetic Survey in the near future; aside from its scientific and practical usefulness in perfecting the Survey of the Coasts. It will eventually be the basis for a precise survey of the whole country, determining boundaries, settling disputes, and furnishing incontrovertible data by which later generations can reproduce the marks placed by the local surveyors who make use of it, should they become obliterated or lost; thereby causing a direct increase in the security of property boundaries, and diminution in litigation that now costs millions of dollars annually. Some of the practical advantages to be derived from such a work, are now being demonstrated in Massachusetts in the "Town boundary Survey," as it is called, in which the corners, or turning points of the boundaries are being determined trigonometrically in a subsidiary work based upon the Geodetic triangulation of the Coast Survey. Each boundary corner in this scheme becomes a fixed point, and the direction and distance of many other corners are at once accurately ascertained in their true relations to it. The town boundaries will in due time be made the bases of referenee for all local surveys and subdivisions of property; so that, eventually, there will be developed a cadastral map of unrivaled excellence, to supplement the Topographical map that has just been completed.

The imperfections of our "land surveys," brilliant as the scheme was conceived to be at the time of its inauguration, demonstrate only too clearly the extravagance of primitive methods in matters intended to be enduring. As time passes and property taken up under the "land survey" becomes more valuable, the difficulty of accurately identifying boundaries becomes more serious, until finally, it is only after long litigation that rights are determined. The inherent defect in the land survey to accomplish the purpose for which it was designed, lies in the fact, that while it parcels out the land, or a section of land, in a given number of lots, it fails to provide the means for identifying the boundaries of the lots at any future time; the marks placed for this purpose become obliterated or perhaps are moved by designing men, until a large area may be involved in great uncertainty. A triangulation covering the same ground and controlled by Geodetic work, determining the true positions of the old marks that may be left, would be the most economical and precise method of relieving these uncertainties and fixing for all time the location and boundaries of the lots originally parcelled out, by observations and marks that cannot be lost or obliterated.

The system of weights and measures in use throughout the country is largely due to the patient labor of the Coast Survey. Required by law to have standards of length, the only bureau in the public service that required such a measure of precision, it was in the natural order of events that the Superintendent of the Survey should also be charged with the maintenance of standards of Weight and Capacity. The duplication of standards for the use of the people was begun under Mr. Hassler, so long ago that the system has really grown with the population. Wise legislation has fostered the sentiment of uniformity until we are indeed blessed, that wherever we may be in all our broad domain, a pound is a pound, a yard is a yard, and a bushel is a bushel. Manufacturers receive their standards from the Bureau, and in special cases have their products tested and certified. And individuals engaged upon work of great refinement, seek the stamp of the Bureau, also, upon the measures on which they must rely. But so careful is the Bureau to preserve the integrity of its certificate, that the stamp is refused except on weights or measures of approved metal and workmanship. Business men realize in every day life the benefits that have been derived from the simple legislation that inaugurated a supervision over the weights and measures of the country early in her history, though they may have no conception of the endless annoyances they would have been subjected to had the preservation and duplication of standards not been provided for.

The limited time assigned to me will not permit a detailed statement of the researches made by the Bureau in all the different branches of science related to the practical conduct of the work, much less a reference, even, to the many improvements instituted in the practice of surveying. As in the case of the observatories called upon to replace their defective instruments with those more refined, to enable them to furnish star places of sufficient precision to meet the improved method of determining latitude, so has the demand ever been upon the experts employed upon the work in all its branches. The Triangulation, Topography, Hydrography, Astronomy and Magnetics have all passed through several stages of development and improvement in methods and instruments, to meet the requirements put forth by those charged with the conduct of the work, that the full measure of harmony desired should be secured and that they might supply the demands made upon them for information. Imperfect results indicate defects to be remedied, and it is to the credit of those who performed the labor, that they overcame one difficulty after another as they were developed, until now the methods and instruments in the hands of experts, will produce far superior results at a much less cost than was possible at the time the Survey was inaugurated.

The charting of the great ocean currents, has long been an interesting investigation to hydrographers the world over. A sketch of the efforts, projects, and devices that have been resorted to by the Coast Survey in the attempt to unravel the mysteries of the Gulf Stream, would exemplify the continuous demand for improvement and new exertions under which those employed upon the work have always labored, although the full measure of knowledge sought has not yet been obtained. But it is not necessary to enter into these details at this time; let it suffice that many experiments and failures pointed out the path to be followed by subsequent observers, and stimulated to new efforts, until at last appliances have been perfected that have already produced wonders, and it is safe to predict, will ere many years show the ocean currents on the charts of the world with the same relative precision that the currents in a river or harbor can now be indicated. Lieutenant Maury gave us current charts that were a marvel in their day, but his information, or data, was defective, and his conclusions, therefore, only approximate; and how to improve on the data he had, has ever since been the subject of research. The depth of the ocean is necessarily an important factor in the study of its features, as erroneous depths lead to false hypotheses. The introduction by the English of a method of sounding with a wire, has therefore proved an important advance. American officers have perfected the apparatus and severely tested the methods, demonstrating the reliability of the results and the total unreliability of the old deep sea soundings taken with a line. These accurate wire soundings have revealed new facts, disproved old theories and formed new ones to guide future researches. So successful is the improved apparatus that specimens of the bottom of the ocean have been brought up from a depth of five miles. The great value of this system, however, is not confined to the mere ascertainment of depths for the hydrographer and cartographer, as may be readily demonstrated by referring to the reports of the Fish Commissioner. A further step towards improving on Maury's results; the crowning glory that is to shed light on much that has been dark, and trace out those ocean currents we have heretofore vainly endeavored to follow, is found in the invention and devices of a naval officer attached to the Survey, whereby he can anchor the ship in mid-ocean and observe the direction and velocity of the current as from a stationary body, and with a "current meter," also his own invention, determine the same factors hundreds of feet below the surface; thus ascertaining not only the movement at the surface, but the depth of the body of water that moves, and the velocity at various depths, so that finally we have the volume―a quantity―to be followed until it meets other currents or is absorbed in the vast expanse. Already current observations have been recorded with the ship anchored at the great depth of eighteen hundred fathoms; and arrangements have been perfected that it is believed will prove successful at the greater depth of three thousand fathoms. It is impossible with our superficial knowledge of the great ocean currents to estimate the benefits that will be derived from their systematic exploration. It is not probable that the absolute determination of their limits would produce such a revolution in navigation, as was caused by Maury's wind charts, but it is reasonably certain they would prove a valuable assistance to the navigator, and in the great channels and bays of the world increase his facilities for the successful navigation of his ship. Not a little of their value, perhaps the larger part, will be of an indirect nature, resulting from their study by investigators in the natural sciences interested in utilizing the bounties of nature for benefit of man.

The Survey was instituted for the determination of facts, and the presentation of them in an intelligible form. It does not promulgate theories, and has no use for them beyond the assistance they may be in indicating the line of research necessary to ascertain the facts; but rather leaves to the student the formulation of the theories that may be deduced from the facts presented. The publications of the Survey are, therefore, calculated to contain only useful, practical information, on the subjects of which they treat. An examination of them will show this to be the case, and further, that error has more likely been committed by over-caution, than a too free use of the material at command. Doubtless much has been suppressed through lack of means, as it has always been the aim of the Superintendents to expend the appropriations in producing the most useful results, whether in surveys to be made or facts to be published. It necessarily requires many years to complete a precise survey over a large area; and in the work of the Coast Survey, with the people in all sections of our extended coast line petitioning for surveys at the same time, the problem was beset with additional difficulties. Fortunately Congress prescribed the method on which the work should be conducted, and that the method permitted making surveys widely separated with the certainty that they could eventually be joined and form a consistent whole. Soon after the plan of reorganization of 1843 had been adopted, surveying parties were on the Atlantic and Gulf coasts at many points; the principal harbors and headlands with outlying shoals were first surveyed and it was but a few years before charts of them were published. The less important shores between these points were left for future work, but Hydrographic examinations or Nautical surveys, were made of them, and preliminary charts of long stretches of coast were issued, to be followed when the surveys had been completed by the finished chart of reliable data. So elastic was the system adopted for the conduct of the work, that its availability was limited only by the annual appropriations. Soon after the annexation of Texas surveying parties were on that coast, and on the acquisition of California a few years subsequently parties were soon at work there also; and after the close of the war and purchase of Alaska, the immense field thus opened was attacked with equal promptness, and a reconnaissance made that resulted in a map of considerable accuracy. As the precise surveys were extended the charts and plans published from the preliminary surveys were withdrawn, the new charts necessarily having later dates.

The original surveys of the Atlantic and Gulf coasts are now practically completed, but very little more remaining to be done in a few comparatively unimportant localities. On the Pacific coast precise surveys supplemented by careful reconnaissance of less important sections, define nearly the whole outline, excepting Alaska, but a great deal of work is still required to obtain the full measure of information necessary to accurately chart it. And in Alaska, Nautical surveys have developed long stretches of the "Inland passage " and the most important anchorages, supplementing the general reconnaissance of the whole coast line. A very large proportion of our shores, however, are subject to such radical changes from natural causes, that the survey of the coast can never be brought to final completion. Examinations and re-surveys are as essential as was the original work, if the material already acquired is to be maintained in the full measure of its usefulness, and commerce is to continue to reap the legitimate benefit of the expenditures already incurred. Fortunately the survey has been conducted on such sound principles it meets the increasing requirements for accuracy demanded by the navigation of to-day, as fully as it did the more simple needs of the navigator of forty years ago, and it is fairly believed, whatever may be the necessities of the future, that it will still supply the information desired.

The Surveys are published in four hundred and fifty charts designed to meet the various needs of the Navigator and Civil Engineer, for either general or local purposes; over thirty thousand copies of these are issued annually and there is a steadily increasing demand.

The assistance rendered to the armies and fleets of the Union, in the late Civil War, is a chapter in the history of the Survey that should not be forgotten. The office in Washington was beset with demands for information from all over the country, for descriptions not of the coast alone, but all sections of the interior representing the seat of war. Fortunately the experts were there who, under the direction of able chiefs, could collect and compile such material as was available. The labor of the office in this cause resulted in the publication of a series of "War Maps" of the interior, for which there is frequent demand even at the present day. This was all additional work to a force already overburdened in the preparation of manuscript maps and special information, compiled from the reports of the Field parties; especially of those localities that had only recently been surveyed. And in all the din and excitement of the call to arms, with hosts of stalwart, honest men assembled around him, that might give in their learning the wisdom of the world, the controlling mind of the Survey, that had labored diligently and sought knowledge patiently, was a chosen counsellor of the Chief of the Nation. Declining military honors, the profession in which he had been educated, he devoted himself with renewed energy to assisting the nation's efforts in those special duties he knew so well how to perform. A patriot himself of the purest type, he inspired those around him by his ennobling spirit and zeal in the cause.

An average of twenty parties were maintained with the Army and Navy during all the years of the war, rendering services of acknowledged value to the military forces. An officer of the Coast Survey piloted the fleet into Port Royal; another led the Iron Clads in the attack on Sumter; a third stationed the fleet in the bombardment of Jackson and St. Philip; and a fourth rendered signal services in the assault on Fort Fisher. They were on the Peninsula, guides in the wilderness on the retreat to Malvern Hill; at Chickamauga, Knoxville, Missionary Ridge; the march to the Sea and pursuit through the Carolinas; on the Red river; before Petersburgh; in the Sounds of North Carolina; the Sea Islands of Georgia and Florida and the swamps of Louisiana; and, wherever they went, few in numbers though they were, they gained honor for their cause and credit for their Chief.

The Survey of the Coast has excited the admiration of the whole civilized world for its thoroughness and accuracy, and has not been excelled by the most advanced nations. It has justly been claimed to be a scientific work, as well as a practical one, for science has guided those who have conducted it and led them through the fields of their labors on the only sure basis to produce knowledge. And the great knowledge that has been acquired by its scientific prosecution, is beyond comparison with the little that would have resulted had it been conducted on the less thorough methods of Nautical Surveying that have been so earnestly advocated. We cannot compute the value of what has been learned in dollars and cents; that it has saved to the Nation many times over, all that it has cost, does not admit of a doubt. Its educational influence has been widespread, extending beyond the seas, and coming back to us with cheering words of encouragement and praise. Practical men utilizing the results of the great work in the business affairs of life, use no stinted phrases in the encomiums they bestow upon it; Military men compelled to rely upon it in the perils of warfare, have not found it wanting, and have given only praise for the great help it was to them; Scientific men, ever watchful of that which is true, have approved it the world over, and cite it as an example of the great profit that may come to a people, free to utilize Science in the conduct of practical work. Our institutions of learning have adopted its publications in text-books. Our merchants venture millions of dollars daily on the veracity of its statements, and our mariners risk their lives on the truthfulness of the Surveys. It has added to the prosperity of the nation in peace—to her glory in war; and when history shall record its awards to our people, there will be no page of the galaxy with more honor than that which bears tribute to the genius of American Science, in the work of the Coast Survey. From ignorance most profound we have been raised to knowledge almost perfect; and well may the commercial communities by their associations and exchanges bear the testimony to its value that they do, and have done in times past; as might the whole people for the wise legislation that established the work, that has defended it, and we may hope will perpetuate it for its inestimable benefits to them all.