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The late eclipse undoubtedly awakened greater interest in this new branch of science.
Prof. Magnus has lately published a research upon heat spectra.
Angström and Thalen have also lately published laborious and accurate tables of the wave lengths of the different metals.
Roscoe's work on Spectrum Analysis, published this year, presents the subject in a very lucid manner.
We incorporate herewith the notes of Mr. Nichols on the progress in the field of chemistry.
In Chemistry no startling discovery has been made during the past year. Yet each year marks progress, especially in the contributions to the history of the compounds of carbon, and each year adds to the number of those complex bodies which, a short time ago, were found only in the bodies of animals or in plants, but which now can be prepared at will, in the laboratory. Especial attention may be called to the production during the past year, by artificial means, of alizarine, the coloring matter of the madder root (vide p. 205). Such discoveries extend our views of the domain of chemistry and cause us to have less apprehension in regard to the limited supply of many substances, the demand for which is continually increasing.
The publication by Professor Bunsen, of Heidelberg, of a paper on the “Washing of Precipitates” (vide p. 210), has wrought a great change in the manner of conducting in the laboratory an operation of constant occurrence, that of filtration. By his method, as contrasted with that formerly employed, the saving of time amounts in certain cases to many hundred per cent., an advantage which, at the present day, we cannot afford to overlook.
The researches of Graham (vide p. 194) on the metallic character of hydrogen as deduced from the deportment of the alloys of palladium and hydrogen show how close is the relation between mechanical force and chemical affinity. It seems as if he were “ led not only to manifest the metallic character of hydrogen, but also to seize the very moment at which the phenomenon of the mechanical condensation of a gas by a porous body changes into a truly chemical combination.”*
The council of the Chemical Society (London) having determined to found an annual lectureship in honor of Faraday, the inaugural lecture was delivered this year (June 18) by the French chemist, Dumas, who was eminently fitted to perform this duty, not only on account of his having been an intimate friend of Faraday, but also on account of his great eloquence, and on account of his eminent position among the chemists of his own country. He began with an admirable eulogy of him whom his discourse commemorated, and then reviewed, from the stand-point of the present day, the progress of chemistry from its first beginnings.
* Dumas. Faraday Lecture.
He paid tribute to the labors of Lavoisier, Dalton, and Prout, and, pointing out the analogies existing between the elements of mineral chemistry and the compound radicals of organic chemistry (so called), and at the same time the relations between the atomic weights of those bodies which are now accepted as elements, he argued the probability of their being themselves proved to be complex,
The limits of chemistry he defines in these words: “The existing chemistry is, therefore, all powerful in the circle of mineral nature, even when its processes are carried on in the heart of the tissues of plants or of animals and at their expense; and she has advanced no further than the chemistry of the ancients in the knowledge of life and in the exact study of living matter; like them she is ignorant of the mode of generation.
“ The apcients were mistaken when they confounded, under the name of organic matter, sugar and alcohol, which have never lived with the living tissue of plants, or in the flesh of animals. Sugar and alcohol have no more share of life than bone-earth, or salts contained in the various liquids. The chemist has never manufactured anything which, near or distant, was susceptible even of the appearance of life. Everything he has made in his laboratories belongs to ó brute'matter; as soon as he approaches life and organization, he is disarmed.”
The medal which accompanies the Faraday lectureship is struck in palladium, and, in addition to this medal, Dumas carries back to France with him a medal struck in the alloy of palladium and hydrogen to commemorate the discovery of the alloy by Graham.
The subject of the disposal of the sewage of towns becomes daily of more importance. At the meeting of the British Association at Exeter, a report was presented, in which were collected statistics showing the various methods adopted in towns and cities on the continent for utilizing the sewage, and that committee has issued circulars to the town authorities throughout England asking for aid in collecting information and in making experiments in regard to this matter. The earth-closet is finding favor, and, no doubt, will eventually supersede the water-closet in rural districts, and in towns where a supply of water cannot readily be obtained. The fact that it has been made the subject of a patent adds to its cost, and will retard somewhat its adoption in this country, but now that attention has been called to the matter, use will be made, and with advantage in a sanitary aspect, of the principle which is involved in it, — the disinfecting power of dry earth.
“Like some other valuable discoveries, it seems surprising that nobody thought of it or applied it before. But the simple fact is, that the privy may be made as inoffensive as the corn-barn by the application of about a pint and a half of dry earth every time it is used. There are one or two things about it important to remember: (1.) It should be earth (not sand or gravel), and should be thoroughly dried by exposure to the sun or otherwise; (2.) The privy-vault should be kept free from rain, from slops, and from excessive moisture of any sort. The more fluid thrown in, the more dry earth required to absorb it. How often it happens that a country hotel or boarding-house, crowded with people, becomes late in the season disgusting and unhealthy from decomposing material when a few shovelsful of dried earth thrown into the privy once a day would remove all offence.” *
It has been proposed for dried earth to substitute charcoal, which would be regenerated by burning. It is stated that one hundred weight of charcoal per month would be sufficient for a closet used by six persons daily. It is not likely, however, that this modification will find extensive adoption, except in localities peculiarly situated."
We incorporate herewith the notes of Dr. Kneeland on the progress in biology:
“The theory of Darwin is steadily progressing in the estimation of naturalists; indeed it may be said to be no longer simply a theory, as it has been demonstrated, in a few instances at least, both in the vegetable and animal kingdom, that natural selection,' or the survival of the fittest, is one of the causes of the existing varieties and so-called species among animals and plants. No naturalist can now presume to sneer at or ignore this and kindred theories, when such men as Lyell, Hooker, Huxley, and Owen reject utterly the doctrine of innumerable special acts of creation, and accept in variously modified forms the development
* Report of Massachusetts State Board of Health, 1870.
of living things by the operation of laws impressed upon them at the beginning. The derivative hypothesis' of Owen, detailed on pp. 267–270, apparently meets the approval of naturalists more generally than any other; this maintains the incessant new development of living beings out of non-living material, and sees the grandeur of creative power, not in the exceptional miracle of one or few original forms of life, but in the daily and hourly calling into existence many fornis by conversion of chemical and physical into vital modes of force; his conclusion is that, from the magnet which chooses between steel and zinc, to the philosopher who chooses between good and evil, the difference is one of degree, not of kind, and that there is no need of assuming a special miracle to account for mental phenomena. •Natural selection' also is operative in the case of men, among whom there is a perpetual survival of the fittest; in the most barbarous conditions of mankind the struggle is almost entirely between individuals; in proportion as civilization has increased among men, it is easy to trace the transference of a great part of the struggle, little by little, from individuals to tribes, nations, leagues, guilds, corporations, societies, and similar combinations; and accompanying this transference has been undeniably the development of the moral qualities and of social virtues.
• The Social Science Associations are actively working out the great problems of moral and physical evils incident to civilization, especially those pertaining to hygienic or sanitary reform. The first step in the moral elevation of a community has been found to be the diffusion of knowledge of sanitary laws; cleanliness and good health are recognized as the best foundations of public prosperity. Hence science is constantly progressing in attempts to secure for the masses of the people cheap and wholesome food, pure air and pure water, ventilation of public buildings and the crowded dwellings of the poor; the removal of sewage, so as not only not to contaminate the earth, air, and water, but to convert it, even in our own houses, into an inodorous and valuable fertilizer, has been successfully accomplished. Fire-extinguishing and life-saving apparatus, both on land and sea, have reached a high degree of efficiency; man is gradually obtaining the mastery over the epidemic diseases which have for ages decimated the human race; and the return from human to vaccine lymph direct from the cow will restore the wavering faith of the public in the efficacy of vaccination, and eventually put a stop to the ravages of small-pox. The recent successful employment of chloral as an anæsthetic, by the stomach instead of the lungs, and its undoubted efficacy as a sedative in nervous diseases and insanity, has drawn the attention of physiological chemists to the nearly unexplored field of the action of medicines by decomposition within the inmost recesses of the body.
Deep-sea dredgings have revealed an extensive and varied range of life at depths heretofore deemed untenanted, and have proved that there is a band of organisms encircling the globe at the bottom of the ocean, — these organisms, too, resembling those found in the immensely remote cretaceous epoch. The amaba, described on p. 294, seems to be one of the links which connect the inorganic with the organic world, its organless tissue being capable of combining physical forces so as to assume organic functions.”
Great advances have been made in celestial chemistry during the year, through the medium of spectrum analysis.
The observations of Huggins' by means of this delicate method have proved that the star Sirius is receding from the earth at the rate of 29.4 miles per second; the observations of Huggins have been confirmed by Father Secchi, made at Rome. It is thought that the results of these and similar observations may one day lead to a determination of the motion of the solar system in space. By the same method of analysis, traces of aqueous vapor have been discovered in some of the planets.
The President of the British Association, in his address at Exeter, thus details Lockyer's discovery:
“ After having observed the remarkable spectrum of the prominences during the total eclipse, it occurred to M. Janssen that the same method might allow the prominences to be detected at any time; and on trial he succeeded in detecting them the very day after the eclipse. The results of his observations were sent by post, and were received shortly after the account of Mr. Lockyer's discovery had been communicated by Mr. De La Rue to the French Academy. In the way hitherto described a prominence is not seen as a whole, but the observer knows when its image is intercepted by the slit; and by varying a little the position of the slit, a series of sections of the prominence are obtained, by putting which together the form of the prominence is deduced. Shortly after Mr. Lockyer's communication of his discovery, Mr. Huggins, who had been independently engaged in the attempt to render the prominences visible by the aid of the spectroscope, succeeded in seeing a prominence as a whole by somewhat widening the slit,