Popular Science Monthly/Volume 42/March 1893/Sketch of Robert Hare

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THE name of Robert Hare, said the American Journal of Science at the time of his death, "has for more than half a century been familiar to men of science as a chemical philosopher, and to the cultivators of the useful arts throughout the civilized world." Dr. Hare was born in Philadelphia, January 17, 1781, and died in the same place, May 15, 1858. His father, the proprietor of a large brewery in Philadelphia, was an Englishman of strong mind, occupying a prominent position in society, and enjoying the confidence of his fellow-citizens. The management of this concern shortly fell into the hands of the son. He was soon drawn away from it, however, by the strength of his predilection for scientific pursuits; and before he was twenty years old he was enrolled as an attendant of the course of lectures on chemistry and physics in Philadelphia, and became a member of the Chemical Society of that city. There he found Priestley, Sybert, and Woodhouse among his associates. To this society he communicated in 1801 a description of the oxyhydrogen blowpipe, which was then called the hydrostatic blowpipe, and which Prof. Silliman, who had been engaged with him in 1802 and 1803 in a series of experiments with the instrument, afterward called the compound blowpipe. On his return from Philadelphia, in 1803, Prof. Silliman constructed for Yale College the first pneumatic trough combining Dr. Hare's invention; an apparatus which was afterward figured and described by Dr. Hare in his memoir on the Fusion of Strontia and the Volatilization of Platinum—a paper which was republished in London and in the Annales de Chimic. This apparatus, according to Prof. Sillirnan, was the earliest and most remarkable of Dr. Hare's original contributions to science. It revealed to the chemical student a source of artificial power far transcending anything he had ever known before; and this, though the facts on which it was based were not unknown.

Lavoisier had directed a jet of oxygen on charcoal and had burned the elements of water together; but even he, and in the face of these experiments, had failed to comprehend the power of this heating apparatus, and it was left for the acumen of Hare to demonstrate it and make it practically applicable. The author of the biography in the American Journal of Science says of it, "In our view, Dr. Hare's merit as a scientific philosopher is more clearly established upon this discovery than upon any other of the numerous contributions he has made to science." Dr. Hare's original experiments were repeated in 1802 and 1803 in the presence of Dr. Priestley and Messrs. Sillirnan, Woodhouse, and others. In recognition of the discovery, Dr. Hare received the Rumford medal from the American Academy of Science at Boston. An attempt was afterward made, in 1819, by Dr. Clarke, of Edinburgh, to rob him of the credit of this discovery; and though he showed that the oxyhydrogen apparatus had been before the public several years, no attention was paid to his protests. The calcium and Drummond lights also furnish instances of most important applications of Dr. Hare's invention, in which no reference is made to him. He himself led the way to these devices by constructing an apparatus on a gigantic scale, with large vessels of wrought iron, capable of sustaining the pressure of the Fairmount Water Works, with which he was able to fuse at one operation nearly two pounds of platinum, with a resultant production of metal greatly purified.

He devoted much labor and skill to the construction of new and improved forms of the voltaic pile; "and it is easy to show," Prof. Sillirnan says, "that owing to his zeal and skill in this department of physics American chemists were enabled to employ with distinguished success, the intense powers of extended series of voltaic couples long in advance of the general use of similar contrivances in Europe."

In 1816 Dr. Hare constructed an instrument called the calorimeter, in which great extent of surface was obtained by combining many large plates of zinc and copper into one series, and plunging the whole at once into a tank of dilute acid. Great magnetic and heating effects were obtained with this instrument, and it was many years before any other voltaic apparatus was constructed in which the movement of so great a volume of heat was attained with so low a projectile or intensive force. By it large rods of iron or platinum were ignited and fused with splendid exhibitions, while the intensity of the current was so low that hardly a visible spark could be made to pass by it through poles of carbon. The magnetic effects were afterward shown by Prof. Henry to be attainable from a single cell, if combined with suitable conductors. Instead of Cruikskank's cumbrous battery of alternating zinc and copper plates, which Davy used in the experiments that resulted in the discovery of the metallic bases of the alkalies, Hare found a way of obtaining a corresponding amount of surface and its resultant power with a single roll of metal, and in 1820 introduced the denagrator, in which any series, however extended, could be instantaneously brought into action or rendered passive, at pleasure. This apparatus consists of a large sheet of copper having several hundred square feet of surface and a similar one of zinc, separated by a piece of felt or cloth saturated with acidulated water, and then rolled up in the form of a cylinder. Faraday bore testimony, in his Experimental Researches, to the merit of this invention when, in 1835, he acknowledged that, having worked exhaustively to perfect the voltaic battery, finding that Hare had anticipated him many years before, and had accomplished all that he had attempted, he at once adopted his instruments, as embodying the best results then possible.

With one of Hare's deflagrators, Prof. Silliman, in 1823, first demonstrated the volatilization and fusion of carbon, a result then considered so extraordinary that it was a considerable time before it was fully credited. It was with these batteries that the first application of voltaic electricity to blasting under water was made in 1831 in experiments conducted under Dr. Hare's direction.

Dr. Hare was also distinguished in chemistry as the author of a process for denarcotizing laudanum, and of a method for detecting minute quantities of opium in solution. He was interested, too, in the discussions of philosophical chemistry, as was most notably shown in the earnestness with which he contested what he conceived were the errors of the salt radical theory.

He made studies in meteorology, and had a theory of whirlwinds and storms founded on an electrical hypothesis, which he opposed to the rotary theory of W. C. Redfield. At the second meeting of the American Association for the Advancement of Science he explained his own views on this subject, while he controverted those of Mr. Redfield. This gentleman was present and heard his remarks, but made no reply then. He was not a speaker, and did not address the public except in writing.

In 1818 Dr. Hare was chosen Professor of Chemistry and Natural Philosophy in William and Mary College, and in the same year was made Professor of Chemistry in the medical department of the University of Pennsylvania. He held the latter position till 1817. His teachings were marked by the originality of his experiments and the extent and variety of the apparatus he employed. He spared no labor or expense in his operations, and, being a handy mechanician, he was able to bestow much ingenuity in the construction of novel devices for experiment and illustration. He accumulated instruments and material with astonishing profusion. To these he added graphic illustrations and lucid descriptions to make his lectures intelligible and interesting. When he resigned his professorship, he gave all the apparatus he had accumulated to the Smithsonian Institution.

He was a man of literary tastes, fond of poetry, and himself wrote verses occasionally. He also sometimes wrote articles on the political and financial questions of the day, and contributed moral essays to the Portfolio, under the signature of "Eldred Grayson."

In person he had a robust frame, a large head, and an imposing figure and presence.

In his family and among his friends, according to Prof. Silliman, he was very kind, and his feelings were generous, amiable, and genial; yet, in the absence of mind occasioned by his habitual abstraction, and when absorbed in thought, his manner was occasionally abrupt. With his keen and active mind, conversation would sometimes seem to awaken him from an intellectual reverie. He had great colloquial powers, but to give them full effect it was necessary that they should be aroused by a great and interesting subject, and the effect was heightened by the injection of antagonism. He would then discourse with commanding ability, and his hearers were generally as ready to listen as he to speak. He was a man of unbounded rectitude, a faithful friend, and a lover of his country and its best interests, without thought of personal emolument or political advancement. He was a voluminous scientific writer. For many years his contributions to the American Journal of Science were more numerous than those of any other correspondent. The full list of them includes about one hundred and fifty articles, in forty-eight volumes of that journal, the record of the titles of which occupies five columns in the General Index of the first fifty volumes. Besides notices of the various substances he discovered or experimented with, and descriptions of apparatus, we find among these articles some that touch the principles of chemical and physical philosophy—as on the nature of acids and salts; concerning Faraday's views on atoms; on chemical nomenclature, a subject which is also discussed in a letter to Berzelius; on some inferences from the phenomena of the spark in Thompson's work on heat and electricity; on the error that electric machines must communicate with the earth; on a new theory of galvanism; on the cause of heat: a reply to Prof. D. Olmsted's views on the materiality of heat; Reply to Matter is Heavy, as demonstrated by W. Whewell; on meteorological topics—storms of the Atlantic coast; reviews of Redfield's theory of storms and of Dove's essay on storms; an account of a storm or tornado in Rhode Island, August, 1838, "and others"; on Causes of Storm, Tornado, and Water-spout; among accounts of experiments and new methods—blasting rocks by galvanic ignition; apparatus for producing ebullition by cold; process for fulminating powder, consisting of cyanogen and calcium; mode of obtaining the specific gravity of gases; analysis of gaseous mixtures; method of dividing glass by friction; and apparatus for decomposition and recomposition of water. He was also author of a Brief View of the Policy and Resources of the United States (1810); Chemical Apparatus and Manipulations (1836); Compendium of the Course of Chemical Instruction in the Medical Department of the University of Pennsylvania (1840); Memoir on the Explosiveness of Niter (1850); and Spiritualism Scientifically Demonstrated (1855).

He was a member of the American Academy of Arts and Sciences and of the American Philosophical Society, and was one of the few life-members of the Smithsonian Institution.

In his geological explorations of the basin of the Red River of the North through six seasons, Mr. Warren Upham has paid careful attention to the geographic limits and relative abundance of both native and introduced plants. "It has been interesting," he says, "to find there the intermingling and the boundaries of species whose principal homes, or geographic range, lie respectively in the direction of the four cardinal points, east and west, and south and north." After describing this diversified vegetation in detail, the author concludes that besides the greater part of our flora which is of northern origin, coming to us from an ancestral flora that probably in the beginning of the Quaternary period occupied continuous land around the globe in high northern latitudes, the plants of the Red River basin include many species derived, as Gray and Watson have shown for a large portion of the flora of California, the Great Basin, and the southern Rocky Mountain region, from the plateau vegetation of Mexico. By the return of a warmer and drier climate in the southwestern United States, following the Ice age of the North, our cactus species, petalostemons, and onagraceæ, many of our composite, the milkweeds, and many more, have been enabled to spread from their original Southwestern and Mexican home-land, becoming a most important element of the flora of all the plains and prairie region to the Saskatchewan and Red Rivers, and gaining a less numerous representation in the wooded country east to the Atlantic coast. How these Northern and Southwestern floras have become intermingled, the geographic limits of separate species, and the gradual changes observable in the specific characters of some of our plants in passing between distant parts of their range, are themes of sufficient interest to repay the careful observations of amateur botanists in all parts of our country. In these directions important additions to botanic science may be made by many who have neither leisure nor ability for valuable biologic study of plants, but who love the search for wild flowers.