Henry, Joseph

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Henry, Joseph

(b. Albany, New York, 17 December, 1797; d. Washington, D.C., 13 May 1878)

physics.

Henry was born to a poor family of Scottish descent and raised as a Presbyterian, a faith he followed throughout his life. His early education was in the elementary schools of Albany and Galway, New York, where he went, prior to his father’s death in 1811, to reside with relatives. Henry was apprenticed to an Albany watchmaker and silversmith a few years later. The theater was his principal interest as an adolescent, until a chance reading of George Gregory’s Popular Lectures on Experimental Philosophy, Astronomy, and Chemistry (London, 1809) turned him to science.

In 1819 Henry enrolled in the Albany Academy and remained there until 1822, with a year off to teach in a rural school in order to support himself. The surviving Academy archives do not explain how an overage pupil gained admittance nor exactly what Henry studied. From the surviving Henry manuscripts and books we know he was schooled at the Academy in mathematics (through integral calculus), chemistry, and natural philosophy. He won the support of his principal, T. Romeyn Beck, who employed Henry as assistant in a series of chemistry lectures in 1823–1824 and later. Henry’s main problem at this period was how to support himself while furthering his development as a scientist. The surviving evidence is not very clear on what he did. For an undetermined period he was a tutor in the household of the van Rensselaers and later taught the elder Henry James. Tradition has him considering the possibility of a medical career. We do know that Henry did odd surveying jobs and that in 1825 he headed a leveling party in the survey of a, projected road from the Hudson River to Lake Erie. In the next year his friends attempted, unsuccessfully, to get Henry an appointment with the Topographical Engineers of the U.S. Army. Shortly afterward he was appointed professor of mathematics and natural philosophy at the Albany Academy, where he remained through October 1832, when he accepted a chair at the College of New Jersey (now Princeton University).

During these formative years at Albany, Henry was engaged in avid reading of works in science and other fields, an activity he continued throughout his life. He sometimes downgraded his Academy education by referring to himself as self-taught, an obvious reference to his efforts at self-improvement. A fair number of standard periodicals and monographs were accessible to Henry, especially since he was the librarian of both the Academy and the Albany Institute of History and Art, the local learned society. In the latter he associated with the leading citizens of the city who had enlightened, but not professional, interests in the sciences. in 1824 he read his first paper, a review of the literature on steam; by 1827 he was doing experiments on his own.

Henry’s earliest known work was in chemistry, in collaboration with Lewis C. Beck, T. Romeyn Beck’s brother. In 1827, when Henry started his work in electricity and magnetism, Beck was also experimenting in this area; but we have no information on the nature of these investigations. By this date Henry’s reading had made him familiar with the work of Davy, Faraday, Ampère, and probably Young, whose wave theory of light influenced Henry’s subsequent views. He also read and annotated Biot on electromagnetism in the Farrar translation (Cambridge, Mass., 1826) shortly after its appearance.

In his lectures at Princeton, Henry avowed that his work on electromagnetism in Albany, leading to the development of powerful electromagnets and the independent discovery of electromagnetic induction, was an application of Ampere’s theories. This is not self-evident from contemporary sources, for Henry was rather reticent about stating his theoretical views; his approach was the unfamiliar one of drawing analogies with terrestrial magnetism. Throughout his career Henry was interested in terrestrial magnetism, meteorology, and other geophysical topics. In this he was part of an active research tradition of the day. When he investigated terrestrial magnetism in Albany, especially the effect of the aurora, Henry used a needle of Hansteen’s which Edward Sabine had sent to James Renwick, Sr., of Columbia College. When he witnessed a demonstration of Oersted’s discovery in 1826, Henry immediately saw it as a way to explain the variation of the needle. From Ampére’s picture of the earth as a great voltaic pile with innumerable layers of materials producing circular currents around the magnetic axis, Henry probably conceived the idea of winding his horseshoe magnet with many strands of wire in parallel, not using a continuous strand as W. Sturgeon and G. Moll had. When Faraday met Henry in 1837, he invited his American colleague to lecture to the Royal Institution on the mathematical theory of electromagnetism, a strange request in light of the near absence of mathematics in Henry’s papers but explicable if Faraday conceived of Henry as being in some sense a follower of Ampère.

Like Faraday before him (and, later, Wheatstone), Henry had by 1830 independently uncovered the sense of Ohm’s law and was engaging, for example, in what we now call impedance matching. He learned of Ohm only in December 1834 and may not have had a full knowledge of the law until 1837, but clearly Henry was extremely adroit in manipulating his equipment to get desired effects of “intensity” (high voltage) and “quantity” (high amperage) at an earlier date. In the Albany experiments he wanted to design devices suitable for classroom demonstrations, that is, to gel large effects from small inputs. Henry’s electromagnets exemplified this on a large scale. When he applied them to demonstrate the longpredicted production of electricity from magnetism, the distinction between Henry and Faraday as experimentalists became evident. Faraday devised ingenious experimental setups to detect small effects; Henry, almost anticlimactically, devised procedures for rendering small effects grossly tangible. In connection with the experimental work on electromagnetic induction, Henry independently discovered self-induction (1832).

From the time of his transfer to Princeton late in 1832 until Henry’s first European trip in 1837, there was a relative diminution of his research, undoubtedly due to the pressure of teaching duties. From 1838 until his appointment as secretary of the Smithsonian Institution in 1846, Henry was extremely active in research, not only in electricity and magnetism but also other areas of physics. His work outside electricity and magnetism is not as well-known or as consequential. Like all his research, these investigations were conducted with skill and imagination. For example, he published papers on capillarity (1839, 1845) and on phosphorescence (1841). In 1845 Henry wrote about the relative radiation of solar spots. of particular interest in understanding his general scientific orientation are the 1846 paper on atomicity and the 1859 paper on the theory of the imponderables. He published several papers on the aurora and on heat. Henry was also greatly interested in color blindness. In his later work for the Light-House Board he did much experimental research on the propagation and detection of light and sound.

While the earliest Princeton work was a continuation of the Albany investigations, there was an enlargement of Henry’s interests in electricity and magnetism. For one thing, he was most conscious of his American predecessor, Benjamin Franklin, even to the point of once using the pseudonym “F.” While carefully stating that both the one and two-fluid theories were mathematically equivalent, he always opted for Franklin, not Ampére. His work at Princeton shows particular concern for integrating the static electricity phenomena of Franklin with the most recent galvanic developments. Another strand in the Princeton experiments was Henry’s efforts to explain physical phenomena in terms of wave phenomena, most likely deriving from Thomas Young.

Williams correctly notes that Henry’s discovery of self-induction was important to him because it fitted his theoretical views, but that it was not particularly crucial to Faraday’s concepts. The direction of Henry’s thought became somewhat apparent in his 1835 paper on the action of a spiral conductor in increasing the intensity of galvanic currents. The paper started out as an affirmation of Henry’s priority in the discovery of self-induction. He then combined induction proper (using Faraday’s findings and his own) with selfinduction to show how these produce a pattern of repulsions yielding an increased effect in spirals. He specifically linked these “magneto-electrical” results to the principles of static induction developed by Cavendish and Poisson. This explanation was then applied to Savary’s report of changes of polarity when magnetic needles were placed at varying distances from a wire in which a current was being transmitted (“Mémoire sur l’aimantation,” in Annales de chimie et de physique,34 [1827], 5–57, 220–221). That is, currents appeared periodically in the air surrounding a current-bearing straight wire as a result of the actions of induction and self-induction. In his 1838 paper on electrodynamic self-induction Henry started out again with self-induction and also cited the Savary paper. In the 1835 paper and this later work on currents of higher orders, there is some suspicion that Henry saw these varying magnetic needles as analogous to the phenomena of terrestrial magnetism.

Henry’s demonstrations in 1838 and later of the induction of successive currents of higher orders was quite in accord with these views and had considerable impact. Faraday noted in his diary for 12 November 1839 that five others in Britain besides himself had received coils from Henry like the ones used in the dynamic induction experiments. Carrying out his program of determining the relationship of static and dynamic electricity, Henry published a long paper on electrodynamic induction in 1840. In 1842 he returned to the consideration of the Leyden jar discharge discussed in his 1838 paper, noting that Savary had reported anomalies. These Henry explained as a backward and forward oscillatory discharge until equilibrium was reached as a complex resultant of inductions and self-inductions. He considered this explanation as original, but it is in Savary’s paper. Henry’s experiments were undertaken to confirm and explain the direction of the various currents induced by Savary from the straight wire. In this paper he reported propagating and detecting electromagnetic effects over great distance. A single spark “is sufficient to disturb perceptibly the electricity of space throughout at least a cube of 400,000 feet capacity” In this paper he also reported that lightning flashes seven or eight miles away strongly magnetized needles in his study. Similar results appear in his interesting 1848 paper on telegraph lines and lightning. As late as 1856 (diary entry of 19 January) Faraday wondered at these reports.

To explain these effects, in 1842 Henry declared himself a believer in an electric plenum. Having started with the desire to use Ampére (and Oersted) to explain terrestrial magnetism, he had first proceeded to laboratory analogues of terrestrial magnetism and of the electrical currents associated with various forms of magnetism.

In these speculations Henry was staunchly Newtonian, conceiving of astronomy as the model science and mechanics as the ultimate analytical tool. For example, although impressed by Bośkovic’’s atomism, he finally rejected it as incompatible with Newton’s laws of motion on the macroscopic level. Henry could not accept Faraday’s field concept because of his belief in central forces acting in a universal fluid. This view was reinforced by his differing interpretation of experiments on electromagnetic effects in vacuums. From observations of the interaction of currents and magnets, Henry expanded his earlier explanation of Savary to conclude that the currents were oscillator)’ wave phenomena exciting equivalent effects in an electrical plenum coincident, if not identical, with the universal ether.

Henry believed that particular disturbances originating in grosser matter produced wavelike oscillations in the plenum, whose manifestations in other, grosser bodies of matter were electricity and magnetism. He then reduced the wave phenomena to mechanical actions in the plenum. To him, static electricity was instantaneous action at a distance arising from the disturbances in the medium produced by gross matter, yielding condensations and rarefaction in the ether/plenum. Dynamic electricity was an actual transfer of part of the ether/plenum, requiring a discrete time interval to restore the equilibrium of the universal medium.

When Henry assumed the secretaryship of the Smithsonian Institution in 1846, he had fairly clear ideas of what he wanted. Certainly no one really knew what a little-known chemist, the natural son of an English duke, meant when he inserted a contingency clause in his will dedicating his estate to an institution in Washington, D.C., for “the increase and diffusion of knowledge.” The debates in Congress and the press over the Smithson bequest disclose an utter confusion of aims. Basic to an understanding of Henry’s ideas as a science administrator is his being a professional physicist at a time when that breed was quite rare in America. Unlike his great British contemporary, Michael Faraday, he had a good knowledge of mathematics and an appreciation of the need to generalize experimental findings into mathematical formulations. Allied with this appreciation of mathematics was a firm, scornful rejection—in print and in private writings—of crude Baconianism as a scientific method. To Henry, forming hypotheses was the essential step in research.

With views so different from the norm of his time and place, Henry arrived at a conception of the scientific community little understood by many of his contemporaries: a small group of trained, dedicated men meeting internationally recognized standards and engaging in free and harmonious intellectual intercourse among themselves. Henry, as secretary of the Smithsonian, attempted to symbolize this ideal in America. His success in forming the Smithsonian according to his ideals is a credit to his astuteness as an administrator and the broad recognition of his preeminence in the American scientific community. This success also rested on the compatibility of Henry’s views with the beliefs of a significant number of educated laymen.

As secretary of the Smithsonian, Henry was not concerned with popularizing science or with education but with supporting research and disseminating findings. He consequently set great store in properly refereeing proposed publications and in furthering cooperation among scientists. One of his earliest moves was to establish an international system for exchange of scientific publications. This interest in scientific information led in 1855 to his suggestion for what later became, with modifications, the RoyalSociety Catalogue of Scientific Papers. He had initially limited the scope to the exact sciences,

Because Henry saw scientific research neglected in America in favor of other human endeavors and was rather pessimistic about the chances of redressing the balance, he and many American scientists well into the twentieth century sounded and acted as though they were a beleaguered minority. In Henry’s administration of the Smithson bequest, a contemporary reader is struck by persistent notes of alarm as the secretary fights off the attempts by Charles C. Jewett to subvert the institution into a national library and fends off well-intentioned efforts to deflecd the endowment to the support of lyceum lectures and a popular museum of science, art, and curiosities of nature and human ingenuity. Not that Henry disapproved of these activities; he was, after all, one of their proponents both as secretary of the Smithsonian and as a good citizen.

Given the modest size of the bequest and the greater popular interest in nonresearch activities, Henry regarded support of research and scholarly publications as a better use of scarce funds. In reaching these conclusions in private discourses and in public justifications, he was forced to consider the relations of science to other branches of human endeavor. In Albany he had written and lectured on the relations of “pure mathematics” to “mixed mathematics” (what we now call physics) in accordance with a traditional view widely held in that day. Clearly, Henry, like many of his contemporaries, favored and looked forward to the conversion of all fields of science, and also the arts, useful and otherwise, to the status of “mixed mathematics.” By this he meant an infusion of rigor, hopefully in the form of mathematics. As secretary, Henry would do what he could to promote this development across the board but would give priority to those fields at or near the desired state of intellectual development. Fiscal considerations here reinforced Henry’s desire to maintain and develop a preferred intellectual model. In his writings he was impelled by his position to champion the idea of the purity of institutions, in the sense of their having specialized functions and motives. He assumed, for example, that research and popularization were incompatible in a single institution. In this belief he diverged markedly from the national practice.

Although Henry often sounded like a proponent of professional specialization, his own work and the program of the Smithsonian never had that kind of purity. Although best-known as a laboratory physicist, he was active in meteorology and other geophysical areas dominated by observation of natural phenomena; one of the institution’s biggest programs was in meteorology. Henry’s most original activity as secretary was to become America’s leading patron of anthropology and ethnology. He read widely in these fields and, for reasons still unclear, was obviously concerned and enthusiastic. Unlike his successor, S. F. Baird, who reduced the funds for the physical sciences, Henry was careful to support research in natural history as well, despite evidences of his reservations about the value of much work in that field. After Darwin published The Origin of Species, Henry regarded natural selection as the best chance yet to give natural history the rigor it had lacked thus far. Rather than limiting the Smithsonian to one scientific field, he insisted on limiting its support to men of professional competence.

Henry was firmly against Smithsonian involvement in applied research, the American environment, in his view, providing more than adequate incentive for such work outside the institution. In taking this position he was not at all like the pure scientists of the next century who inhabited ivory towers; the record is replete with instances of concern with applications. What Henry was upholding was the logically anterior role of pure science, the assumption of chronological priority following naturally from that position. In the one public priority squabble of his life, with S. F. B. Morse over the telegraph, he was asserting the primacy of disinterested scientific research seeking general truths over investigations of specific practical solutions. While this assertion was quite odd to most of Henry’s contemporaries, American scientists up to the present would implicitly echo him in urging greater support for pure research.

In his relations with the U.S. government Henry also struck a note persisting down to the present. Although very successful in gaining support in Congress and in the executive branch, he continually worried about political patronage forcing ill-trained men on scientific organizations and directing research into unworthy channels. Ironically, this lack of faith in both the government and the society at large inhibited Henry from buttressing the original bequest by seeking additional funds. Lacking a sound financial base dedicated to Henry’s program, the Smithsonian Institution grew in directions not contemplated by him, the new growth largely obliterating his original conception. What did survive was a belief in research.

BIBLIOGRAPHY

I. Original Works. Joseph Henry’s unpublished correspondence and other MSS constitute a major source for the study of his life, as well as for the various topics in which he played a significant role. Under the sponsorship of the American Philosophical Society, the National Academy of Sciences, and the Smithsonian Institution, these widely scattered documents are being gathered for publication under the editorship of Nathan Reingold of the Smithsonian Institution. They will eventually number 50,000–60,000 and include runs of scientific and personal correspondence, Henry’s laboratory journals, diaries, texts of unpublished lectures and articles, and a splendid miscellany of other items. Fifteen printed vols. of selected MSS will appear; the entire body of documentation will be issued as a microfilm publication well before the printed vols. have run their course. The Henry Papers staff is describing and indexing the documents using a computer system, the first such use for a document publication.

In custody of the Henry Papers staff is Henry’s personal library, containing approximately 1,200 monographic and serial titles and approximately 1,200 pamphlet titles. Many items are presentation copies and others bear annotations. since the library includes volumes dating back to the Albany period, historians have available a splendid slice of scientific and other literature closely linked to a large body of unpublished MSS. The library is also being cataloged by computer.

Until the new ed. of Henry’s scientific writings (in preparation under the editorship of Charles Weiner) appears the principal source for Henry’s publications is Scientific Writings of Joseph Henry, 2 vols. (Washington, D.C., 1886). Still the best published bibliography is W. B. Taylor, Memorial of Joseph Henry (see below), pp. 365–374. Taylor’s work was the basis for the Scientific Writings. While the Weiner ed. will not literally reproduce the text of 1886—excisions and additions are contemplated—it will largely follow the old pattern, especially in limiting the contents mainly to the scientific publications. Two restrictive boundary conditions are worth noting: (1) although some items are slated for reprinting in the Weincr ed., for practical reasons there will be no attempt to gather in all such, especially nonscientific pieces; (2) a large body of Henry writings is largely excluded from the 1886 ed. and the Weiner ed.Reports of the Board of Regents of the Smith sonian indian Institution, 1846–1877—in which Henry wrote exnsively and interestingly about his organization, the progress of science, and science’s role in the American republic. In the Scientific Writings (and in the forthcoming ed.) is Henry’s one attempt at a comprehensive treatise, often overlooked because of its misleading title, “Meteorology in Its Connection With Agriculture” (Scientific Writings, II, 6–402) appeared in five parts from 1855 to 1859 as appendixes to the Report of the Commissioner of Patents Despite its title, it is really a general survey of the physical sciences, with only occasional attempts to relate weather and farming. Although nontechnical, the work is not really popular science as we now understand the term. The work merits careful study as a mature statement of Henry’s beliefs and attitudes.

Secondary Literature. The best recent discussion of Henry the scientist is in Charles Weiner’s dissertation at Case Institute of Technology, “Joseph Henry’s Lectures on Natural Philosophy” (Cleveland, 1965). The most recent discussion of Henry’s policies at the Smithsonian Institution is Wilcomb E. Washburn, “Joseph Henry’s Conception of the Purpose of the Smithsonian Institution,” in Walter Muir Whitehill, ed.,A Cab/net of Curiosities (Charlottesville, Va., 1967), pp. 106–166. Recent articles concerning Henry are L. Pearce Williams, “The Simultaneous Discovery of Electro-magnetic Induction by Michael Faraday and Joseph Henry,” in Bulletin de la Société des amis d’André-Marie Ampère, no. 22 (Jan. 1965), 12–21; and T. K. Simpson, “Maxwell and the Direct Experimental Test of His Electromagnetic Theory,” in Isis, 57 (1966), 411–432. Henry is discussed and some of his MSS printed in N. Reingold, ed., Science in Nineteenth Century America, a Documentary History (New York. 1964), pp. 59–107, 127–161, 200–225. Two recent biographies of his American contemporaries are superb for background on Henry; A. Hunter Dupree, Asa Gray (Cambridge, Mass., 1959); and Edward Lurie, Louis Agassiz, a Life in Science (Chicago, 1960). L. Pearce Williams, Michael Faraday (New York, 1965), has only a few references but is indispensable for an understanding of Henry, as is A. Hunter Dupree, Science in the Federal Government (Cambridge, Mass., 1957).

There is an extensive, older hagiographic literature whose most recent and respectable exemplar is Thomas Coulson, Joseph Henry, His Life and Work (Princeton, 1950). Coulson’s work is based upon examination of a limited body of the extant primary sources and relies heavily upon the unpublished draft of a biography of her father by Mary Henry. It has many errors of omission and commission, its principal defect being a lack of knowledge about Henry’s America. Besides Mary Henry’s work, with its attempt to revive priority battles Henry never fought, the hagiographic literature has two additional sources: sentimental homages by American scientists and engineers to their distinguished predecessor and quasi-historical literature emanating from the Smithsonian. The former is best forgotten except by students of scientific mythology. Two of the works in the latter genre are still useful if used with care: W. J. Rhees, ed., The Smithsonian Institution: Documents Relative to Its Origin and History, 1835–1899, 2 vols. (Washington, D.C., 1901); and. Memorial of Joseph Henry (Washington, D.C., 1880), the former (and a companion volume of documents on the regents of the institution) for many years the principal published source on the early history of the Smithsonian. The latter is filled with undocumented bits of information on Henry’s life. It and the Mary Henry draft in the Smithsonian Archives are often the only sources for the charming and possibly true stories about Henry’s early years.

Nathan Reingold

Henry, Joseph (1797-1878)

views updated Jun 08 2018

Joseph Henry (1797-1878)

Source

Physicist

Early Years. Joseph Henry was born in Albany, New York, in 1797. His working-class family often struggled for money, and in his early teens Henry began working as a store clerk. He also served as an apprentice to a jeweler and watchmaker, and in his extra time he acted and wrote plays for an amateur theatrical group. Reading a popular book on natural science, he became so fascinated by the subject that he committed himself to becoming a scientist. He studied assiduously, was admitted as a student at the Albany Academy, and in 1826 became professor of mathematics and natural philosophy at that institution.

Henrys Early Experiments. As a professor Henry made important advances in the study of electromagnetism. A British scientist, William Sturgeon, had invented the electromagnet in 1825, but Henry improved the device to its present-day form. Sturgeon had wrapped bare copper wire around a bar of soft iron; when a current was sent through the wire, the iron produced enough magnetic force to lift a nine-pound piece of iron or steel. By using insulated rather than bare wire Henry was able to lift heavier weights. Like Henry, the British scientist Michael Faraday experimented with electromagnetism. In 1831 Faraday discovered that the iron core of the electromagnet, when moved in and out of its surrounding copper coils, produced electricity in the wirea phenomenon known as electromagnetic induction. It appears that Henry had discovered induction before Faraday but failed to publish his observations; he did not do so until three months after Faradays findings appeared in the April 1832 issue of Uve Annals of Philosophy. The work of both men was important for the development of the electric-power industry in the nineteenth century.

Telegraphic Experiments. During his years at the Albany Academy, Henry also discovered that the arrangement of the wire coils of an electromagnet affected its strength and durability. Using two different coil arrangements, he created two electromagnets, which he called a quantity magnet and an intensity magnet. Using the intensity magnet, Henry transmitted signals through a wire three miles in length. He published his findings in the American Journal of Science in 1831. Later in the 1830s Samuel Morse improved on Henrys device by inventing the relay, which allowed the signal to be transmitted over longer distances, and the Morse Code, which made it possible for letters to be translated into electrical impulses and vice versa. Morse patented this invention in 1844 as the telegraph.

Other Inventions. Henry also invented an electric motor while at Albany Academy. He balanced an electromagnetic bar horizontally on a pivot; below each end of the bar was a vertical permanent magnet. Two wires extended from each end of the bar; when the bar was tilted in either direction the wires on that end made contact with the terminals of a battery, thereby sending current through the wires and producing magnetism in the bar. The permanent magnet on that end was arranged so that the pole nearest the bar was of the same polarity as that end of the electromagnet; since magnets of the same polarity repel each other, the bar would tilt the other way, breaking the connection with the battery on that end and establishing a connection with the battery on the other end. That end of the bar would then be repelled by the permanent magnet below it, and the electromagnet would tilt back the other way, and so on. During one experiment the oscillation continued for more than an hour. In 1832 Henry accepted a professorship in natural philosophy at the College of New Jersey in Princeton, where he not only continued to make important discoveries in electromagnetism but also conducted studies in solar physics and other branches of physics.

The Smithsonian Institution. When the Englishman John Smithson, who had never been to America, died in 1829 he bequeathed more than half a million dollars to the United States to found an institution for the increase and diffusion of knowledge among men. Congress established the Smithsonian Institution in 1846, and Henry, the best-known scientist in America at the time, was named as its secretary, or head. Throughout his tenure Henry emphasized the necessity of original research, ensuring that the Smithsonian would be not just a natural science museum but a research institution. He introduced such innovations as the production of weather forecasts (especially storm warnings) based on reports of weather conditions obtained by telegraph. Henry remained secretary of the Smithsonian until his death in 1878. He also helped establish the American Association for the Advancement of Science in 1847 and served as president of this organization from 1868 until he died.

Sources

Thomas Couison, Joseph Henry: His Life and Work (Princeton: Princeton University Press, 1950);

Bernard Jaffe, Joseph Henry, in his Men of Science in America: The Role of Science in the Growth of Our Country (New York: Simon &, Schuster, 1944).

Henry, Joseph (1797-1878)

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Joseph Henry (1797-1878)

Source

Physicist

Beginnings. Joseph Henry was born in Albany, New York, to William and Ann Alexander Henry. His father, a day laborer, died young. When he was seven his impoverished mother sent him to live with her stepmother in Galway, New York. He attended district school and at age ten began to work in a local general store. His biographer maintained that Henry showed little evidence of intellectual greatness as a boy. He did, however, develop a taste for reading when he discovered the village library. His love for science was sparked by a chance encounter at age sixteen with a book on experimental philosophy, astronomy, and chemistry. After reading that book Henry determined to go to college and pursue the study of science. Soon thereafter he returned to Albany. His indifferent education had not prepared him for college, so he worked by day and attended classes at the Albany Academy by night. After only seven months of study he was able to pass the exams for graduation. From about 1814 to 1816 he became tutor to the children of Stephen Van Rensselaer. He subsequently supported himself by working as a surveyor for the state of New York and by teaching at the Albany Academy.

Electromagnetic Researches. Henry taught at the Albany Academy from 1826 to 1832. It was during that time that he began his research into electromagnetism. He discovered the induced current independently of British scientist Michael Faraday, although Faraday announced his results first, in a paper presented before the Royal Society on 24 November 1831. Henry read the paper in the Annals of Philosophy the following June. He subsequently published his own results in the American Journal of Science to further publicize and confirm Faradays discoveries. The discovery of electromagnetic induction, as developed and described by both Henry and Faraday, was critical to the development of long-distance telegraphy, the electric motor, and the transformer.

Views on Technology. Henry emphasized the importance of abstract, or theoretical, science at a time when it was not fashionable to do so. He nevertheless believed that technology and science were closely related and argued in favor of developing that relationship. He saw that bringing pure science into the service of technological progress would highlight the value of such seemingly abstract work. He best expressed his ideas in this regard in a lecture delivered in Albany in 1832 titled On the Theory and Practice of Science, in which he said:

The mechanic arts, upon proper reflection, must awaken the curiosity and the interest of all who are dependent upon them for the necessaries or the luxuries of life and these will comprise every member of the civilized part of mankind. The advancement also of these arts must be felt as an object of great importance to both nations and individuals. Now without the application of correct scientific knowledge to this purpose they must ever remain stationary or their advance be extremely slow. This position will appear evident when we reflect that every mechanic art is based upon some principle or one of the general laws of nature, and that the more intimately acquainted we are with these laws the more capable we must be to advance and improve the arts.

This philosophy governed Henrys approach to scientific research and education for his entire career.

Princeton Years. In 1832 the College of New Jersey at Princeton appointed Joseph Henry professor of natural philosophy, a position that he held until 1846. At Princeton he continued his research into electricity and developed a national and international reputation as a scientist and teacher. He also became a vocal advocate of professionalization, supporting the recognition and strict enforcement of academic qualifications for scientists. To this end he became a member of the American Philosophical Society in 1835, helped to organize the American Association for the Advancement of Science in 1847, and was a founding member and president of the National Academy of Sciences, established in 1866.

Smithsonian Institution. The reputation that Henry acquired at Princeton resulted in his selection in 1846 as the first secretary of the newly established Smithsonian Institution. He proved a skillful administrator, although his new responsibilities forced him to give up research. His influence was paramount in shaping the Smithsonian Institution as an organization that promoted original research for the increase of knowledge and the international dissemination of that knowledge for the general advancement of science and other disciplines.

Source

Thomas Coulson, Joseph Henry, His Life and Work (Princeton, N.J.: Princeton University Press, 1950).

Joseph Henry

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Joseph Henry

Joseph Henry (1797-1878), American physicist and electrical experimenter, was primarily important for his role in the institutional development of science in America.

Joseph Henry was born Dec. 17, 1797, in Albany, N. Y. He attended the common school until the age of 14, when he was apprenticed to a jeweler. He later studied at the Albany Academy and in 1826 became professor of mathematics there. He immediately began researching a comparatively new field—the relation of electric currents to magnetism. The important result of this work was Henry's discovery of induced currents. In 1832 he was appointed professor of natural philosophy (chemistry and physics) in the College of New Jersey at Princeton.

In 1846 Henry became the first secretary and director of the Smithsonian Institution in Washington, D.C., a position he held for the rest of his life. Under his direction the institution encouraged and supported original research. Although a large portion of the income settled on the institution by Congress was for the support of the museum, art gallery, laboratory, and library, Henry took every opportunity to divest the institution of such burdens.

As the Smithsonian's director, Henry acted as one of the major coordinators of government science. Among the projects he originated was the system of receiving simultaneous weather reports by telegraph and basing weather predictions on them. From these beginnings came the U.S. Weather Bureau. During the Civil War he served on the Navy's permanent commission to evaluate inventions and on the Lighthouse Board.

Henry was elected to the American Philosophical Society in 1835. He helped organize the American Association for the Advancement of Science in 1847 and was an original member of the National Academy of Sciences, chartered by Congress in 1863. He became vice president of the National Academy in 1866 and was president from 1868 until his death. He was responsible for reorganizing the academy and transforming it from a society that emphasized governmental service to an honorary organization which recognized "original research."

Henry died on May 13, 1878. By concurrent resolution a memorial service was held in his honor on the evening of Jan. 16, 1879, in the hall of the House of Representatives, and by act of Congress a bronze statue was erected at Washington in his memory.

Further Reading

The only modern biography of Henry is Thomas Coulson, Joseph Henry: His Life and Work (1950), a largely uncritical account that does not adequately stress Henry's institutional contributions. Detailed accounts of Henry's life and work are in James Gerald Crowther, Famous American Men of Science (1937); Bernard Jaffe, Men of Science in America (1944; rev. ed. 1958); and Bessie Zaban Jones, ed., The Golden Age of Science, containing a memoir by Asa Gray (1966). Henry's career and influence are discussed at length in Paul Henry Oehser, Sons of Science: The Story of the Smithsonian Institution and Its Leaders (1949), and Bessie Zaban Jones, Lighthouse of the Skies: The Smithsonian Astrophysical Observatory: Background and History, 1846-1955 (1965). A Memorial of Joseph Henry, containing several biographical sketches and a complete bibliography, was published by order of Congress in 1880 (published also as Smithsonian Miscellaneous Collections, vol. 21, 1887). □

Joseph Henry

views updated May 11 2018

Joseph Henry

1797-1878

American physicist whose experiments with electricity led to the development of electromagnets, which in turn made possible the electric motor. In honor of this work, the unit of inductance is called the henry. As first secretary of the Smithsonian Institution, Henry resisted congressional pressure to turn that organization into a passive repository of knowledge, insisting that the Smithsonian also support original scientific research.

Henry, Joseph

views updated May 18 2018

Henry, Joseph (1797–1878) US physicist, whose work on electromagnetism was essential for the development of the telegraph. His work on induction led to the production of the transformer. The unit of inductance is named after him.