TILL within a comparatively recent time, geologists regarded the climate of the prehistoric periods as tropical or warm temperate. Those who first sought to explain the presence of certain scratches upon ledges, by the action of moving ice in continental masses scouring the surface, were met by ridicule and skepticism.
TRANSLATED FROM THE FRENCH, BY J. FITZGERALD, A.M.
IN the former part of this essay we considered the general physiology of the passions: their pathology is no less interesting, and to that we now ask attention. When we reflect that the nervous system of the animal life and the system of the great sympathetic govern all the vital operations, and that the regularity of these latter is absolutely dependent on the orderly performance of their functions by the centres wherein are found the prime springs and the fundamental activities of the animal economy, we conceive at once how countless diseases may arise out of disturbances produced by an abuse or an excess of the passions.
SO much has been said lately of the wonders of spectrum analysis, that we are very apt to forget the other and equally marvelous properties of the agent by which it is produced. Spectrum analysis is a rare and curious experiment, but the more familiar effects of light which we daily experience are really just as wonderful, if we will but pause to reflect upon them.
PROFESSOR OF PHYSIOLOGY IN THE UNIVERSITY OF CAMBRIDGE.
MICHAEL FOSTER, M. D., F. R. S.
IN the following pages I propose to inquire whether it is desirable that physiologists should continue the practice of what is commonly called vivisection, to which they have hitherto been accustomed. By vivisection I understand the operating with cutting instruments or by other means on the still living bodies of animals.
ALTHOUGH not by a balloon, yet the Atlantic has been crossed in the air, and “ what has been can be.” There are enough well-authenticated cases of the occurrence of American wild birds on the west coast of Europe to prove that the trip can be made by birds, and it is probable that successful navigation of the air will be the fruit of careful study of that natural flying-machine, a bird’s wing.
IT is a general rule that substances can crystallize only while solidifying from the liquid state of either fusion or solution. The only exceptions are, that some few substances crystallize directly from their vapors without passing through the intermediate liquid form.
THE importance of establishing a first meridian for the United States at the seat of government, in connection with a National Observatory for the purpose of systematic scientific observation, attracted the attention of Congress as early as 1810.
SPECIES of insects known as Mantids belong to the order Orthoptera, which includes crickets, grasshoppers, cockroaches, locusts, etc. The following figure illustrates the appearance of one of these. They are of bright, variegated colors, and are sometimes quite large, even three or four inches in length.
YEAR by year the word “Evolution” becomes diffused more widely through our literature, and the central idea which it implies grows familiar to an ever-increasing multitude of readers. We have witnessed within the last few years a marvelous awakening of interest in the minds of the public generally to questions of science, and it so happens that a discussion of the doctrine of Evolution has been more or less directly involved in those departments of Science and Philosophy which have during this period received the largest share of popular attention.
THE mind of animals is a very old subject of discussion. Descartes and his school regarded an animal as a mere piece of machinery, like a clock or a turnspit. For man alone they reserved intelligence, meaning by that, memory, feeling, will, and reason.
AT the annual meeting of the American Geographical Society, held on the 13th of January, 1874, the address was delivered by the President of the Society, Chief-Justice Daly, who gave to a large and intelligent audience an admirable digest of geographical work and progress during the past year.
THOMAS HENRY HUXLEY was born at Ealing, on May 4, 1825. With the exception of two and a half years spent at the semi-public school at Ealing, of which his father was one of the masters, his education was carried on at home, and in his later boyhood was chiefly the result of his own efforts.
OUR very common “ mud - minnow ” (Melanura limi, Agassiz — Silliman's American Journal of Science, 1853, vol. xvi., p.135), which is found over a wide extent of territory in America, and which, according to Dr. Albert Gunther (“ Catalogue of Fishes,” in the British Museum, vol.
THE present number closes the second year and the fourth volume of THE POPULAR SCIENCE MONTHLY. That it met a demand is shown by the fact that it has been better sustained than any other scientific magazine of its class that has been started in any country.
THE study of the human mind is beyond all doubt one of the most sublime and important, as it is certainly one of the most difficult, of all studies. So great is its interest that it has fascinated philosophers for thousands of years, and so great is its difficulty that of all branches of inquiry it has proved least amenable to investigation, and has led to the most discordant conclusions.
ics.—In his - sketch of the growth of the science of thermodynamics, Prof. P. G. Tait, of the University of Edinburgh, rates the services of Count Rumford second in importance to those of Davy, and does not apparently eonsider them comparable to those of Joule.
IN an article on “ Furs and their Wearers,” published in the December POPULAR SCIENCE MONTHLY, the fur-seal of Alaska and the sea-otter were inadvertently confounded. In a letter kindly calling attention to the error, Mr. F. M. King, of Whitestone, L. I., who has been on the spot and knows the two animals, points out a few of their chai’acteristic differences.