Popular Science Monthly/Volume 9/July 1876/A Fitting Recognition of American Science

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AT the six hundred and eighty-ninth meeting of this body, held March 8, 1876, the chairman of the Rumford Committee introduced the special business of the evening, and handed to the President, Hon. Charles Francis Adams, the Rumford medals (in gold and silver), on each of which had been engraved the following inscription: "Awarded by the American Academy of Arts and Sciences to John W. Draper, for his researches in radiant energy, May 25, 1875." In presenting the medals the President said:

Gentlemen of the Academy: The foundation of this Society, you all know, dates back but four years less than a century. It followed close upon the adoption of the form of government of the State itself. Further than this privilege of a corporation, I am not aware that the State has since bestowed any aid on it whatever. During the long period that has intervened, the individual members have steadily and honestly contributed their labors and their money to the advancement of science and of the arts, the evidence of which is to be found as well in the collections of the library as in the long series of their published transactions. We have not been so lucky as to earn the favor of the generous and wealthy at all in the proportion given to some other institutions of the same general character. In point of fact, we have to ascribe our success more to our own energies than to the assistance of patrons. This is no bad sign for the future. The Academy was never in more healthy and vigorous condition than at this moment. The meetings are constantly attended by members who appear to give or to receive with interest the many valuable contributions to knowledge which ultimately take their place in the formidable volumes open to the inspection of the world.

Yet it is not to be understood from what I have said that the institution has been altogether without liberal assistance from several sources. The most remarkable instance of a benefaction was perhaps the earliest, that of Benjamin Thompson, better known under the name of Count Rumford, who, eighty years ago, presented to the Academy the sum of five thousand dollars, to be devoted to the stimulation of the study of the various phenomena connected with light and heat, by the presentation of medals of value as honorary rewards to successful research. It is to the credit of the Academy, in these degenerate days, to find that its administration of this property has fully justified the confidence of the donor, the original sum having increased more than fourfold over and above the cost of the medals which have from time to time been awarded to successful investigation of the great subjects proposed for study and examination.

It now becomes my agreeable duty to announce the fact that, after a careful review of the meritorious service of Prof. Draper in this great field of inquiry, the committee having the subject in their charge have, for reasons given by them, recommended through their chairman, that the medals prescribed in the deed of trust should be presented to him as having fully deserved them. It falls to my lot only to recapitulate in brief some of these reasons.

In 1840 Dr. Draper independently discovered the peculiar phenomena commonly known as Moser's images, which are formed when a medal or coin is placed upon a polished surface of glass or metal. These images remain, as it were, latent, until a vapor is allowed to condense upon the surface, when the image is developed and becomes visible.

At a later period he devised the method of measuring the intensity of the chemical action of light, afterward perfected and employed by Bunsen and Roscoe in their elaborate investigations. This method consists in exposing to the source of light a mixture of equal volumes of chlorine and hydrogen gases. Combination takes place more or less rapidly, and the intensity of the chemical action of the light is measured by the diminution in volume. No other known method compares with this in accuracy, and most valuable results have been obtained by its use.

In an elaborate investigation, published in 1847, Dr. Draper established experimentally the following important facts:

1. All solid substances, and probably liquids, become incandescent at the same temperature.

2. The thermometric point at which substances become red-hot is about 977° Fahr.

3. The spectrum of an incandescent solid is continuous; it contains neither bright nor dark fixed lines.

4. From common temperatures nearly up to 977° Fahr., the rays emitted by a solid are invisible. At that temperature they are red, and, the heat of the incandescing body being made continuously to increase, other rays are added, increasing in refrangibility as the temperature rises.

5. While the addition of rays so much the more refrangible as the temperature is higher is taking place, there is an increase in the intensity of those already existing. Thirteen years afterward Kirchhoff published his celebrated memoir on the relations between the coefficients of emission and absorption of bodies for. light and heat, in which he established mathematically the same facts, and announced them as new.

6. Dr. Draper claims, and we believe with justice, to have been the first to apply the daguerreotype process to taking portraits.

7. Dr. Draper applied ruled glasses and specula to produce spectra for the study of the chemical action of light. The employment of ruled metallic specula for this purpose enabled him to avoid the absorbent action of glass and other transparent media, as well as to establish the points of maximum and minimum intensity with reference to portions of the spectrum defined by their wave-lengths. He obtained also the advantage of employing a normal spectrum in place of one which is abnormally condensed at one end and expanded at the other.

8. We owe to him valuable and original researches on the nature of the rays absorbed in the growth of plants in sunlight. These researches prove that the maximum action is produced by the yellow rays, and they have been fully confirmed by more recent investigations.

9. We owe to him, further, an elaborate discussion of the chemical action of light, supported in a great measure by his own experiments, and proving conclusively, and, as we believe, for the first time, that rays of all wave-lengths are capable of producing chemical changes, and that too little account has hitherto been taken of the nature of the substance in which the decomposition is produced.

10. Finally, Dr. Draper has recently published researches on the distribution of heat in the spectrum, which are of the highest interest, and which have largely contributed to the advancement of our knowledge of the subject of radiant energy.

And now, in the absence of Dr. Draper, unable at this inclement season to execute a fatiguing journey, it gives me pleasure to recognize you, Mr. Quincy, as his worthy and competent representative.

I pray you, in receiving these two medals on his behalf, in accordance with the terms of. the original trust, to assure him, on the part of the Academy, of the high satisfaction taken by all its Fellows in doing honor to those who, like him, take a prominent rank in the advance of science throughout the world.

Mr. Quincy, on receiving the medals, said:

Mr. President: In the name and on the behalf of Dr. Draper I have the honor to receive the Rumford medals in gold and silver, which the Academy has been pleased to award to him, and I will have them safely conveyed to him to-morrow, together with the assurances of the satisfaction of the Academy in this action which you wish me to communicate to him. In common with yourself, sir, and all the Fellows present, I regret that that eminent person is unable to attend this meeting and receive the medals himself. And, personally, I regret the absence of Dr. Wolcott Gibbs, who had promised to perform this grateful service for his friend, and who would have been able to make a more suitable reply to the able discourse with which you have accompanied the presentation of the medals, and to have done more justice to the claims of Dr. Draper to this distinction than I can pretend to do. Dr. Gibbs having also been unavoidably prevented from being present this evening, I have now the honor to read a communication from Dr. Draper to the Academy, in acknowledgment of this testimony to his services to science.

Mr. Quincy then read the following letter:

To the American Academy of Arts and Sciences: Your favorable appreciation of my researches on radiations, expressed to-day by the award of the Rumford medals, the highest testimonial of approbation that American science has to bestow on those who have devoted themselves to the enlargement of knowledge, is to me a most acceptable return for the attention I have given to that subject through a period of more than forty years, and I deeply regret that through ill-health I am unable to receive it in person.

Sir David Brewster, to whom science is under so many obligations for the discoveries he made, once said to me that the solar-spectrum is a world in itself, and that the study of it will never be completed. His remark is perfectly just.

But the spectrum is only a single manifestation of that infinite ether which
makes known to us the presence of the universe, and in which whatever exists—if I may be permitted to say so—lives and moves and has its being.

What object, then, can be offered to us more worthy of contemplation than the attributes of this intermedium between ourselves and the outer world?

Its existence, the modes of motion through it, its transverse vibrations, their creation of the ideas of light and colors in the mind, the interferences of its waves, polarization, the conception of radiations and their physical and chemical effects—these have occupied the thoughts of men of the highest order. The observational powers of science have been greatly extended through the consequent invention of those grand instruments, the telescope, the microscope, the spectrometer. Through these we have obtained more majestic views of the nature of the universe. Through these we are able to contemplate the structure and genesis of other systems of worlds, and are gathering information as to the chemical constitution and history of the stars.

In this noble advancement of science you, through some of your members, have taken no inconspicuous part. It adds impressively to the honor you have this day conferred on me, that your action is the deliberate determination of competent, severe, impartial judges. I cannot adequately express my feelings of gratitude in such a presence, publicly pronouncing its approval on what I have done.

I am, gentlemen, very truly yours,John W. Draper.