Popular Science Monthly/Volume 8/April 1876/Miscellany
Trichinous Pork.—Trichina spiralis was first discovered by Owen, in 1835, in human muscular tissue. Some twenty years later the parasite, as seen by Owen, namely, as a minute worm coiled up within a cyst, was found by Herbst to be the larva of a thread-like worm. The latter passes its life in the intestinal canal, the former inhabits the muscular tissue. When the flesh of animals infested by the larvæ is taken into the stomach, the immature trichinae quickly multiply, and in the course of a few days millions of the encysted larvæ may be found in the muscles. As has been shrewdly conjectured, it is not Improbable that the prohibition of pork as food, a prohibition enforced not only among the Jews, but among various races inhabiting widely-separate regions of the earth, had its origin in an observation of injurious consequences attending the use of swine's flesh. Dr. Sutton's "Report on Trichinosis," noticed in our January number, is worthy of the attention, not only of medical men, but of the public. We give herewith the result of his observations on the cases of the disease which came under his notice, and of his examination of hundreds of specimens of pork:
1. He found that all the cases which came under his observation were produced by eating uncooked or imperfectly-cooked pork. 2. He reiterates the uniform teaching of medical observers that the vitality of the trichinæ can be destroyed only by thorough cooking of the meat, and that the eating of merely smoked or dried pork is dangerous. 3. From microscopic examinations of pork killed in Southeastern Indiana, he found from three to sixteen per cent, of the hogs affected with trichinæ, the number of hogs diseased varying greatly in different localities. 4. That ninety per cent, of the disease produced by trichinous pork appears as gastero-enteritis, diarrhœa, or dysentery, ten per cent, only representing the cases of trichinosis proper.
Penetrating Power of Different Colored Lights.—An experiment was lately made at Trieste, to determine how far lights of different colors penetrate darkness. Half a dozen lanterns with carefully-selected glass, and all furnished with oil and wicks of the same quality, were lighted on the beach, and then observations were made by a party in a boat. At the distance of half a league, the dark-blue lantern was invisible, and the deep-blue one nearly so; hence it appears that blue lights are not adapted for use in lighthouses, or as signals. Of all the colors the green was visible for the longest distance, with the exception of the red, which ranked next to the white in power of penetration. The conclusion is, that only the green and the red are suitable for signals; and the green light the Trieste observers only recommend for use in conjunction with white and red lights, inasmuch as, when viewed from a short distance, an isolated green light begins to look like a white one.
Curious Freak of the Curly-Willow.—The following curious facts are communicated by Dr. S. Lockwood to the Botanical Bulletin: "We have two pendent willows, known as Salix Babylonica (more correctly S. pendula, Mœnch.), the weeping-willow, and Salix crispa, the curly-willow. On the grounds of Hon. E. W. Scudder, Trenton, New Jersey, is a fine specimen of each, the two having a clear distance of twenty-five feet between their nearest branches. The topmost branch of the curly-willow, on the side of the tree next the weeper, is about ten feet long, and six feet thick, and is densely covered with leaves. The curious fact is, that while the rest of this entire tree has the perfect habit of S. crispa, this large branch has the perfect habit of S. Babylonica. The long pendent branchlets, and every leaf, are in all respects those of the weeping-willow. This is true not only of the form and habit of the leaves, but with positive exactness also of the color. The true crispa leaves are a very dark and shiny green above, and almost a chalky white underneath. The pseudo-Babylonica leaves are a pale yellowish-green above, and still paler, perhaps pea-green, on their under sides. I compared them carefully with the leaves of the neighboring Babylonica, and, excepting perhaps that the leaves of the freak were a little the smaller, a fact of no significance, there was no difference whatever. Looking at this great branch, the spectator comes to regard it as a natural graft. This is an utter mistake. It is purely an outcropping of heredity, and is thus an interesting evidence of the identity of species in the curly and the weeping willow. Supposing S. Babylonica to be the ancestor, we have here the long-dormant inherited force asserting itself, and proclaiming the ancient and wellnigh lost parentage of S. crispa. It is observable, too, that the foliage of the branch, thus representing the true weeper, is much more dense than that on the rest of the tree representing the curly-willow. This is the fact respecting these trees everywhere. The curly-willow has this to its disadvantage, its paucity of foliage, so that, in pointing back to its ancestry, it declares the leaf-wealth of the ancient line. As the tree is a very old one, it is significant that this declaration of heredity should appear so late in life."
A Wise Public Benefactor.—In 1868 Sir Joseph Whitworth presented to the British nation an annuity of £3,000 per year, which was vested in the Department of Science and Art, for the purpose of founding scholarships to promote the instruction of young men in the theory and practice of mechanics and the cognate sciences. He has now made over to the public his large landed estates for similar purposes, reserving to himself a life interest. The Department of Science and Art is to hold the estates, subject to the control of Parliament. In commenting upon this munificent action of Sir Joseph Whitworth, the London Times commends his wisdom in trusting Parliament to adapt his endowment to the varying circumstances of successive times. "We have had," says the Times, "abundant instances of late years of the manner in which what the Lord-Chancellor describes as a 'perpetual trust' has hampered, instead of fostering, the development of the future. It is not merely that so much money has been wasted, but obsolete rules and exploded systems have been a lasting obstacle to the growth of thought and to the intelligent adaptation of new generations to new necessities. The law of mortmain has not been sufficient to avert this danger, and great institutions like our universities and public schools have from time to time come to a dead-lock. Being established with no other dominant object in view than that of perpetuating the systems of the past, a troublesome outcry has always been raised when it has become necessary to adapt them to the present."
Diffusion of Cholera.—Pettenkofer's theory of the spread of cholera—namely, that it depends on geological and hydrological conditions—receives confirmation from the researches of Dr. Decaisne, one of the foremost hygienists of France. In a communication to the Académie des Sciences, Dr. Decaisne calls attention to the fact that the cities of Lyons and Versailles have always been in a great measure proof against this disease, though the country round about has again and again been ravaged by it. Paris, on the contrary, has often suffered severely from cholera. In 1832 Lyons entirely escaped the visitation of the epidemic, which ravaged all the rest of the country. Again, in 1835, Lyons was not attacked by the cholera in its advance up the Rhone. In 1849 it made its appearance in one of the barracks, and a few cases occurred in the neighborhood; but three weeks later it had disappeared. In the autumn of 1853 the cholera prevailed in the department of Drôme; there was an outbreak at Lyons, the number of cases being 400, with 196 deaths. In 1865 there were only a few sporadic cases.
According to Pettenkofer's theory, the immunity of Lyons is explained partly by the constitution of the soil, but this explanation applies only to those quarters of the town which overlie the granite rock, either directly, or with a bed of clay interposed. All those portions of the city which rest on the alluvium owe their immunity to peculiar conditions of the underground water. The two instances mentioned above of outbreaks of the cholera in Lyons coincide with periods of exceptional drought, when organic matter, which is usually submerged, underwent decomposition by the action of the air. But those portions of the city which owe their salubrity to the physical constitution of the soil have always enjoyed immunity. As for the city of Versailles, the conditions there are analogous to those found at Lyons. But Paris rests on Eocene Tertiary formations which are permeable and dry—conditions which are favorable to the dissemination of cholera,
Coal-Deposits in New York State.—In a recent popular lecture on the subject of coal, given under the auspices of the Buffalo Society of Natural Sciences, Prof. A. R. Grote speaks as follows of the prospects of finding coal within the limits of the State of New York: "Though coal exists in small quantities in the earth below the carboniferous formation, it will not pay to mine it. The Marcellus shale, for instance, is so charged with bitumen that it can be burnt. A great deal of money has been wasted in this State in searching for coal in formations where it could not be found. More money, a thousand times over, has been frittered away than would pay for a new scientific survey of the State, which is so much needed. Instead of consulting scientific men, geologists, people have dug vainly, and wasted time, labor, and money. Within the borders of our State we have no carboniferous formations, except a bare outcropping, in the southwestern part, of conglomerate belonging to the series. No coal exists in this State in any quantity."
Observations on the Migrations of Birds.—With a view to ascertain the conditions governing the migrations of birds and certain other periodical phenomena, the natural-history editor of Forest and Stream invites the attention of observers throughout the country to the subject, and suggests that each one keep a record of his observations. The points to be specially observed are the following: 1. Whether each species of birds is resident throughout the year, is a summer or winter visitant, or only passes over a locality in spring or fall. 2. With reference to each species in a given locality, whether it is "abundant," "somewhat common," or "rare." 3. What species breed, and whether more than once in a season. 4. Dates of arrival, greatest abundance, nest-building, laying eggs, hatching of young, and beginning of departure of each species, and when it is last seen in the fall. 5. What effects, if any, upon the relative abundance of particular birds, in retarding their arrival or hastening their departure, sudden changes of the weather, storms, and late and early seasons appear to have. 6. Similar notes upon the appearance and movements of the quadrupeds, reptiles, and fishes of the region, and upon the time of flowering of trees and plants. 7. Other occurrences considered noteworthy. It is desirable that records of this kind should be kept. As the writer in Forest and Stream observes, it is through such observations as these, continued year after year, that the natural history of England has become so well known, and so many persons there have become interested in it. We may add that children might easily be induced to take an interest in this kind of natural-history observations, and so by degrees acquire the faculty of accurately noting what is going on around them.
Arctic Research.—A commission of thirteen eminent naturalists, appointed by the German Government to discuss the question of Arctic discovery, have made a report, in which they adopt the advice of Lieutenant Payer, of the Austrian Expedition. They do not object to Arctic research, but dissuade from voyages of discovery; they believe that the advantages to be derived from the former can be secured by a safer and surer method. They recommend the establishment of permanent stations in those Arctic regions which can be safely approached and abandoned at any time. As a beginning, they recommend several stations to be formed on the eastern shore of Greenland, the western shore of Spitzbergen, and Jan Mayen Island. Houses should be built, furnished with every regard to the inclemency of the climate. In each house the commission would have stationed a detachment of scholars, sailors, and other enterprising men, to remain for a term of years, a ship being sent out for their relief from time to time.
The men at these stations could do good work for meteorology, by observing the periodic recurrence of Arctic phenomena, as well as any deviation from the ordinary rule, and would thus be enabled to discover the reasons for the alternation of storm and calm at the equator. The connection between terrestrial magnetism and atmospheric electricity, cable-currents, and the aurora borealis, can only be investigated in such high latitudes; while the laws of terrestrial magnetism itself will never be thoroughly appreciated unless the variations of magnetism in the far north are studied. Then as to astronomy, the theory of refraction, the atmospheric lines of the spectrum, and the relation between comets and shooting-stars, to be better known, require continued observation near the pole. Geodesy, too, by measurement of degrees and observation of the pendulum, will arrive at more definite conclusions respecting the form of the globe.
Geography, independently of the topographical details to be ascertained on the spot, will derive the most valuable geognostic information from further systematic study. Geology, paleontology, mineralogy, botany, and zoölogy, may expect to make great strides from persistent exploration of the northern and southern poles, while physiology and biology will be enormously advanced by the discovery of the conditions of life in those cold regions. There was a time when man in Central Europe led the life to which Lapps and Eskimos are condemned nowadays. To become familiar with the manners and customs, the religion and morals, the physical and psychical peculiarities of Arctic races, is to dive into the distant past, and may probably explain much that is still unintelligible in our primeval history.
Force and Work.—Work without implies work within. No exercise of force can be made except by the generation and use of force of which no part enters into the external result. The use of muscles involves use of nerves. The external force, if exerted by a muscle, is only part of that which it produces. Now, the proportion between these two in their several degrees is a subject of great practical importance, and some interesting facts have recently been published by Helmholtz. From these it is clear that the greater the external force exerted the greater is the proportion of the needful internal force—that is, great exertion is more wasteful than moderate exertion. Then force has to be evolved in proportion to the external work done, and therefore the greater is the wear and tear of the animal machine. The same increased proportion of non-productive work is seen when the external energy is below a moderate amount. It is found, for instance, that in walking, a speed of three miles an hour gives the most economical use of the forces. No doubt in these facts we have an index to much of the ill effects of the present high-pressure rate of work and life. The waste of force is out of proportion to the work done. More is effected in a given time, but the body feels it more, and its working period is proportionately shorter. These facts cannot be too often repeated or too constantly remembered by those who have the regulation of labor.—Lancet.
Contributions to Meteorology.—The American Journal of Science, for January, contains the fourth paper by Prof. Loomis, giving results of recent researches in the science of meteorology, founded on data derived chiefly from the weather-maps of the United States Signal Service.
In a former article attention was called to the fact that low temperatures at the surface of the earth are produced by descent of cold air from the upper regions of the atmosphere. It was shown that, in areas of high barometer, the movement of the air is outward from the centre, instead of inward, as in case of low barometer or storm. This implies a supply from downward motion.
The current notion, that extreme cold is brought by wind from colder areas, is met by the fact that, at Yakootsk, in Siberia, which is about the coldest place in the Northern Hemisphere, the temperature is lowest when the air is quite still, and equally when the wind is from north, south, east, or west. These results are obtained from four years' observations at that place, and are similar to those obtained at New Haven, except as to direction of wind. It would be difficult to explain where the extreme cold of Yakootsk came from, except from the upper atmosphere, seeing that it is colder than the country round about.
A diurnal variation in the progress of storms was noticed by Prof. Loomis in a former paper. This fact suggested to him the further one that there is a diurnal inequality in the rainfall. This is now shown by observations made at Philadelphia, not by the Signal Service maps, which do not record hourly observations. It appears that the maximum rainfall occurs at about six o'clock in the afternoon; and the minimum at three o'clock in the morning.
By observations which cover a period of ten years, made at Prague, in Bohemia, it appears that the greatest rainfall during the day occurs in the afternoon, the maximum being from three until six o'clock.
The tracks of storms in America and Europe, already noticed by Prof. Loomis, are further considered in this paper. He determined the precise latitude at which the storm-centres cross certain lines of longitude, and in this way establishes a line which is the track of the storm-centre; a similar method was applied to storms in Europe. It appears that the average track is not regular, but varies. In an article published in July, 1874, it was stated that the average direction of the storms of the United States was, for the year, 8° north of east, and that is correct as a general statement. Connected with the present article is a chart, by which it is seen that the average track of American storm-centres is over Chicago and Detroit, and is deflected to the south coast of Newfoundland. From this point it seems to be continuous over the ocean, being deflected northward near the Irish coast, passes over Dublin, and thence across Denmark. These results, however, are obtained from the Paris maps, and the continuity of the line may, in some measure, depend on the extent of the field of observations by which it was determined.
The number of storms traced across the Atlantic Ocean is not large; they undergo changes on the ocean, and frequently are merged in other storms.
The velocity with which storms advance is further considered in this paper. It was previously stated that the rate might vary from a stationary condition for many hours, or several days, to the extreme velocity of 1,200 miles in a day, or even 57.5 miles an hour.
By an examination of European maps it appears that storms over Europe travel at an average rate of 26.7 miles per hour, and it was found from examination of American maps that they move at about the same rate in this country. But over the Atlantic Ocean the movement is only 19.6 miles, showing that the velocity is less over the ocean than over the land.
This proves that the progress of a storm is not merely a drifting of the atmosphere; for, observes the professor, it seems probable that the average progress of the atmosphere in an easterly direction is as rapid over the Atlantic Ocean as it is over North America.
How Rats and Mice use their Tails.—To test the correctness of the popular belief that rats and mice use their tails for feeding purposes, when the food to be eaten is contained in vessels too narrow to admit the entire body of the animal, a writer in Nature made the following experiments: Into a couple of preserve-bottles with narrow necks he put as much semi-liquid fruit-jelly as filled them within three inches of the top. The bottles were then covered with bladder, and set in a place frequented by rats. Next morning the covering of each bottle had a small hole gnawed in it, and the level of the jelly was lowered to an extent about equal to the length of a rat's tail if inserted in the hole. The next experiment was still more decisive. The bottles were refilled to the extent of half an inch above the level left by the rats, a disk of moist paper laid upon the surface, and the bottles covered as before. The bottles were now laid aside in a place unfrequented by rats, until a good crop of mould had grown upon one of the moistened disks of paper. This bottle was then transferred to the place infested by the rats. Next morning the bladder had again been eaten through at one edge, and upon the mould were numerous and distinct tracings of the rats' tails, evidently caused by the animals sweeping their tails about in the endeavor to find a hole in the paper.
Experiments in Beet-Culture.—In the course of their experiments on beet-culture, Dehérain and Fremy planted some beets in absolutely sterile soils, to which were added from time to time such substances as were thought to be essential for the development of the plant. It was found that the beets continued in the rudimentary state when they received in such soils only distilled water; they increased slightly in weight when common water took the place of distilled; their development was greater still when the water contained soluble phosphates, or salts of potash; but yet the roots never attained the weight of 100 grammes. When for these mineral substances were substituted ammoniacal salts or nitrates, the yield was much better. Normal beets, however, cannot be grown unless to these nitrogenous fertilizers are added phosphates and potash salts. It is worthy of note that, when the beet finds in the soil nitrogen, phosphorus, potash, and lime, it develops as well as in a soil containing humus. To establish this point Messrs. Dehérain and Fremy compared the produce of two such soils, and found that the beets grown in sterile soil were heavier than those grown in rich soil.
On examining the beets grown in plots in the experimental garden of the museum, the authors found them to be very poor in sugar, though the soil was very rich. From this it follows that deficiency of sugar in the beet is not due to exhaustion of the soil. In seeking the true cause, it occurred to Messrs. Dehérain and Fremy to ascertain how much nitrogen the beets contained, and found it to be very large. Hence it appeared that a soil rich in nitrogeneous matters is unfavorable to the production of sugar. This conclusion was confirmed by sundry analyses of beets grown at the museum, at the school of Grignon, and in the departments of Aisne, Nord, and Eure. All the results positively confirm the observations made by the authors, and their conclusion is that, if beets are now less rich in sugar than formerly in those departments which have long produced them, that fact is not owing to the exhaustion of the soil and its deprivation of principles necessary for the development of the beet; on the contrary, the reason of the phenomenon is, that the soil is too rich in nitrogenous matters, in consequence of the liberal use of manures.
Balloons and Carrier-Pigeons.—It is related by a writer in the London Quarterly Review for July, that when Pilâtre de Rozier had descended safely to the earth, after making the first aërial voyage ever undertaken by man, Benjamin Franklin, who at the time (November 21, 1783) was in Paris, on being asked his opinion of the brothers Montgolfier's invention, replied, "A child has just been born." But hitherto its growth has been extremely slow. Nevertheless, the history of aërial navigation is full of interest, and it is well told by the writer in the Quarterly. Some of the early objections against ballooning were singular enough. Thus, it was urged that female honor and virtue would be in continual peril, if access could be had by balloons at all hours to the windows of houses! Politicians objected that, if the path of air were to be made free, all limits of property and frontiers of nations would be destroyed. As a matter of course, aërial navigation was denounced as "impious." And, when the brave Pilâtre des Rozier's balloon took fire in the air over the city of Boulogne, and he lost his life, many a one recognized herein the "hand of Providence," just as the peasant-girl, who saw a deal chair fall "from heaven," at once decided that it was a part of the household furniture of the angels. In point of fact, Gay-Lussac, who happened at the time to be overhead, had thrown the chair out of his car, to lighten his aërostat.
During the siege of Paris by the Germans, a balloon post was established in the city. At first there appeared to be innumerable obstacles in the way of this enterprise, the chief one being the difficulty of obtaining a sufficient number of aëronauts. In this strait, the aid of seafaring men resident in the city was invoked, as their training had made them familiar with operations and dangers akin to those of ballooning. From September to January, sixty-four balloons were sent off, and of these fifty-seven fulfilled their mission. The number of letters thus dispatched was 3,000,000. The writer in the Quarterly Review mentions one incident connected with these balloon voyages which seems hardly credible: On one. occasion, the crew of a balloon found themselves over the sea, out of sight of land. Seeing vessels they made signals for help, but were not answered, and one vessel fired on them. The men afterward descended to the earth in Norway.
To carry dispatches and letters into Paris, carrier-pigeons were employed. The dispatches, public and private, were first printed on pages of folio size, 16 of which were placed side by side, forming a large sheet about 54 inches long by 32 wide. This was reduced by photography to 1 of its original area, the impression being taken on a small pellicle of collodion, two inches long and 11 wide, and weighing about 3 of a grain; each contained about 2,000 words, or 32,000 words in all, equal to about 58 pages of this magazine. Every pigeon carried twenty of these leaves, which were carefully rolled up and put in a quill. At the Government office in Paris, the quill was cut open, and the collodion leaves carefully extracted. They were then magnified by an optical apparatus, copied, and sent to their destination.
Mental Overwork.—One of the great evils of modern life, in the estimation of many eminent physicians, is mental overwork. It is asserted that affections of the heart are now more numerous than ever before, that asylums for the insane are being overcrowded, and that nervous disorders of every kind are on the increase. What are the signs which indicate impairment by overwork? This question is thus answered in the Sanitary Record: "Overwork," says the Record, "exists when the sense of energy once possessed is distinctly impaired; when it is found an effort to get through what was once a cheerful task; when what was once found comparatively easy is beginning to be felt a trial; and above all when errors or omissions, the direct outcomes of a flagging and wearied brain, commence to manifest themselves. To spur on an exhausted brain, and by application and longer hours of toil to compel the overtaxed nervous system to complete its round of duty, is one of the most disastrous and erroneous measures that can be adopted. Whenever work, itself unaltered, looks larger than of yore, and is felt to be more trying, then the system is commencing to feel the effects of overwork, which, however, may actually have existed for some time unnoticed. This is especially true of the monotonous labor which is undergone by the clerks and subordinate officials of our commercial houses; if they are free from the anxieties which affect the principals, they are the more subject to the wearing action of monotonous labor. The institution of bank holidays is a step in the right direction, and ere long the absolute necessity for a more decided increase in the number of national holidays will be palpable enough. What man can safely do is not to be measured by his desires, but by his powers; and we are all rapidly becoming convinced that incessant toil is not only undesirable, but that it is uneconomical. The one day's rest in seven is not now sufficient for our needs."
French Public Libraries.—In a statistical work, comparing France with other European countries, the following interesting notes on public libraries occur: Paris has six great libraries, the property of the state, and open to the public, viz.: Bibliothèque Nationale (900,000 volumes), Bibliothèque Mazarine, Bibliothèque de l'Arsenal, Bibliothèque Sainte-Geneviève, Bibliothèque de la Sorbonne. Outside of Paris France has 338 libraries which twenty years ago contained 3,689,000 printed volumes. Forty-one of these libraries are open in the evening. Great Britain has (in its public libraries) 1,771,493 volumes, or six volumes per 100 of the population; Italy 11.7 volumes per 100. In France there are 4,389,000 volumes, or 11.7 per 100 persons; in Austria 2,488,000 volumes, or 6.9 per 100; Prussia 2,040,450, or 11 per 100; Russia 852,000, or 1.3 per 100; Belgium 509,100, or 10.4 per 100. Since 1865 school libraries have been founded nearly throughout all France. We have already in the Monthly given the statistics of these school libraries, but we copy the figures again from the work to which we are indebted for the foregoing statistics. In 1865 there were 4,833 of these school libraries in France, containing 180,854 volumes; in 1866, 7,789 libraries, 258,724 volumes; 1867, 11,417 libraries, 721,853 volumes; 1868, 12,395 libraries, 988,728 volumes; 1869, 14,395 libraries, 1,239,165 volumes; 1870-'71, 13,638 libraries, 1,158,742 volumes.
Appearances attending the Passage of a Meteor.—In stating the results of his observations on the passage of a meteorite seen at Louisville, December 12, 1872, Prof. J. Lawrence Smith says that it first appeared as a large red light in the zenith, which seemed to stand motionless for several seconds, evidently because it was then descending in a line with the eye of the observer. Then starting off with an uncertain, faltering motion, it moved slowly toward the horizon, gradually fading from a lurid red to a dark purplish hue, and leaving a dense stream of blue smoke behind, which remained for several minutes. "These clouds," continues Prof. Smith, "are not unfrequently connected with the passage of these bodies through our atmosphere, and are usually more striking in the daytime, or, as in this instance, just after sunset, when the sun was well situated to light up the cloud and exhibit it to the observer who could no longer see the sun. What are these clouds? Are they composed of impalpable matter abraded from the surface of these bodies in their passage, or are they true vapor-clouds? From a close study of observations in connection with several well-known falls of meteorites, I am more inclined to adopt the former view; but there is reason for believing that the violent disturbance of a portion of the atmosphere (much of it, in the rapid passage of the body, undergoing great condensation), added to an undoubted electric disturbance of the atmosphere, would tend to the deposition of moisture, upon the atmosphere being gradually restored to its former equilibrium."
Insect-killing Plants.—During a botanical tour in Atlantic County, New Jersey, Mr. Meehan, of Philadelphia, found growing, near Hammonton, a great number of plants representing three species of Drosera, namely, D. filiformis, D. longifolia, and D. rotundifolia. All of these species had insects attached to them, but many of the plants had none. The remains of the insects which have been caught seem to continue attached to the plant for a long time, and thus the observer at once perceives which plant has had the benefit of animal food. No difference in health or vigor could be detected between those which had had insects and those which had not. This, however, does not by any means decide the question whether the plants do or do not digest the insects. As Mr. Meehan remarks, the case of these plants is comparable to that of vegetarians and flesh-eaters among mankind; it is a question which class is the healthier. A plant, he said, might feed on insects, and yet be no healthier than those which lived as other plants did. But the author does not see how this faculty of catching and digesting insects could be developed by natural selection. "It is believed," said he,"that the power to catch insects is a developed one—a power not possessed by their predecessors—and developed according to the law of natural selection. Unless insect-catching can be shown to be an especial advantage, there is nothing to select." Among the many Droseras observed by Mr. Meehan on this occasion, only one presented the phenomenon of the leaf bending over on itself, and so enfolding the prey.
The Soda-Lakes of Wyoming.—An account of the soda-lakes of Wyoming Territory is given in the report of Mr. Pontez, geologist of the Union Pacific Railroad. He describes two such lakes, the larger one covering about 200 acres. The average depth of water in this lake is three feet, and its specific gravity 1.097. The soda is nearly all carbonate. The second lake is situated near the first, and covers about 31 acres. During the greater part of the year it is a concrete mass of carbonate-of-soda crystals. Mr. Pontez excavated to the depth of six feet without reaching the bottom of the deposit, which is constantly increasing from the influx from the larger lake. These lakes are situated about 65 miles from Rawlins Station, on the Union Pacific Railroad. The quality of the carbonate is declared to be fully equal to the imported article. Estimating the quantity by the specific gravity of the water, its depth and area, the large lake would yield on evaporation 78,000 tons, which would realize, at $45 per ton, 4,510,000. Besides the cost of freight, the expense of preparing the article for market would be $4 per ton for evaporating. The small lake already crystallized, and estimated only at a depth of six feet and an area of 155,000 feet, contains 30,660 tons, which at $45 per ton would realize $1,379,700.
Refraction of Sound.—Refraction of sound by the atmosphere was the subject of a paper read by Prof Osborne Reynolds, at the last meeting of the British Association, in which were given the results of experiments made by the author. He had confirmed his hypothesis that when sound proceeds in a direction contrary to that of the wind it is not destroyed or stopped by the wind, but that it is lifted; and that at sufficiently high elevations it could be heard at as great distances as in other directions, or as when there is no wind. An upward diminution of temperature had been proved by Glaisher's balloon-ascents, and he showed, by experiments with the sounds of firing of rockets and guns, that the upward variation of temperature had a great effect on the distance at which sounds could be heard. By other observations, he found that when the sky was cloudy and there was no dew, the sound could invariably be heard much farther with than against the wind, but that, when the sky was clear and there was a heavy dew, the sound could be heard as far against a light wind as with it.
The Opium-Habit.—The British vice-consul at Kinkiang, China, in a report to his government, states certain facts coming under his own observation, which seem to show that the opium-habit may exist without detriment to health. During a tour on the Upper Yang-tse-kiang, he was thrown into the closest relations with junk-sailors and others, almost every adult of whom smoked opium. Their work was of the hardest, rising at 4 a. m., and working, with hardly any intermission, till dark, having constantly to strip and plunge into the stream in all seasons. The quantity of food eaten by them was prodigious, and from this and their work it may be inferred that their constitution was robust. The two most addicted to the habit were the pilot and the cook. On the incessant watchfulness and steady nerve of the former the safety of the junk and all on board frequently depended; the other worked hard from 3 a. m. to 10 p. m., and often longer. This cook had a conserve of opium and sugar, which he chewed during the day, as he was able to smoke only at night.