experimenting with hydrogen-in the presence of MM. Berthelot, H. SainteClaire Deville, and Mascart-M. Cailletet succeeded in observing indications of its liquefaction under conditions of proof which left no doubt in the minds of the scientific men who witnessed the experiment. It was repeated a great number of times. Operating with pure hydrogen compressed to about 280 atmospheres, and then suddenly allowed to expand, they saw form an extremely attenuated and subtle mist suspended in the gas and disappearing suddenly. Having liquefied nitrogen and oxygen, the liquefaction of air is thereby demonstrated. It appeared, however, of interest to make this the subject of an actual experiment, and, as might be expected, it succeeded perfectly. I need not say that the air was previously dried and freed from carbonic acid. The accuracy of the views expressed by the founder of modern chemistry, Lavoisier, is thus confirmed as to the possibility of causing air to assume the liquid state, and of producing matter gifted with new and unknown properties. At a recent meeting of the Académie des Sciences M. Lecoq de Boisbaudran exhibited a bar, a sheet, and several crystals of the new metal, Gallium, which is harder than iron, yet melts at under the heat of the finger, its freezing-point being at about 30°. It is proposed to use it for a thermometer going up to red-heat. 5000 kilogrms. of ore had to be worked down to get 60 grms. of metal. It will now be possible to investigate its physical properties. It adheres to glass, and is very brittle; the colour is nearly that of steel; and the crystals are octahedra. M. Lecoq de Boisbaudran has since determined the atomic weight of gallium; it is 69.9. A photo-lithographic plat of the primary triangulation carried on during the summer of 1877, by Mr. A. D. Wilson, Chief Topographer, has just been published by the U.S. Geological Survey, under the charge of Dr. F. V. Hayden. The area covered by these triangles extends from Fort Steele, in Wyoming, Zy., westward to Ogden, in Utah, Zy., a distance of about 260 miles, and north as far as the Grand Teton, near the Yellowstone National Park, including Fremont's Peak, of the Wind River Range of the Rocky Mountains. The area embraces about 28,000 square miles, and within it twenty-six primary stations were occupied and their positions accurately computed. Besides these occupied stations a large number of mountain peaks were located, which in the future will be occupied as points for the extension of the topographical work of the Survey. A base line was carefully measured near Rawlins' Springs, on the line of the Union Pacific R.R., and from this initial base the work was extended north and west to the valley of Bear River, in Idaho, Zy. Here a check base was measured, and the system expanded to the neighbouring mountain peaks, to connect with the triangulation, as brought forward from the first-mentioned base. Along the line of the Union Pacific R.R. the work was connected at six points with the Triangulation System of Clarence King's 40th Parallel Survey. In addition to the importance of this sheet as the base of the season's topographical work, it presents a most striking feature in the number of remarkably long sights which were taken from some of the most lofty mountains in the area explored. Many of these sights were over 100 miles in length, while some reach a distance of 135 miles. From Wind River Peak all the prominent points in the Big Horn Mountain were sighted; also the loftier peaks of the Uinta Mountains: the former are located 165 miles to the north-east, while the Uinta Mountains are situated about the same distance to the south-west. As these ranges were not in the scope of the season's work they are not given on the chart. CONTENTS OF No. LIX. I. THE SENSES OF THE LOWER ANIMALS. II. THE SUPERFICIAL GRAVELS AND CLAYS AROUND FINCHLEY, EALING, AND BRENTFORD. By Thomas Belt, F.G.S. III. ON THE POSSIBILITY OF EXPLAINING PAST CHANGES IN FIC NOTICES OF SCIENTIFIC WORKS. Wright's" Metals and their Chief Industrial Applications." Skertchly's "The Physical System of the Universe, an Outline PAGE 410 411 412 413 414 415 "Ure's Dictionary of Arts, Manufactures, and Mining." "Proceedings of the Literary and Philosophical Society of "Bulletin of the United States Geological and Geographical Survey of the Territories." "Records of the Geological Survey of India." "Reports of the United States Geological Survey of the Territories." Kardec's "Heaven and Hell, or the Divine Justice Vindicated in the Plurality of Existences." 415 416 417 419 421 Including Proceedings of Learned Societies at Home and Abroad, and Notices of Recent Scientific Literature JOURNAL OF SCIENCE. JULY, 1878. I. THE SENSES OF THE LOWER ANIMALS. XPANDING the aspiration of the Scottish poet, most of us at times crave to see, not merely ourselves, but the whole world as it appears to the senses of others. We cannot help questioning what portion of our perceptions is purely objective, depending solely on the nature of the things seen, heard, or tasted, and what portion, if any, is due to our own subjectivity, and is consequently liable to vary in different individuals? For instance, we see the flower of a field poppy. It impresses our retina with a certain sensation which we have been taught to call "redness." We can find in the solar spectrum, or in Chevreul's chromatic circles, regions which make upon us the like impression. Our neighbour, unless affected with colour-blindness, gives the same name to the effect produced by the flower upon his sight.* But who guarantees, after all, that the impressions made respectively upon him and upon us are identical? Neither of us can make use of the optic nerves of the other. Much more strongely does this doubt crop up as regards the senses of smell or taste. One of the most familiar facts in daily life is to find one man praising an odour or a flavour which is to another person simply loathsome. Where lies the difference? In the very impressions made upon the nerves of smell and taste, or in the judgment formed by some inward faculty on reviewing such impressions? But if we have already grounds for question as to whether our sensuous perceptions are identical with those of our fellow-men, the difficulty * It has been pointed out that persons suffering from colour-blindness have often great facility in accommodating their language to that of their colourdiscerning neighbours, and thus, unless systematically tested, often escape detection. Many persons who are red colour-blind do not merely fail to distinguish red from its complementary green, but red light, as light seems to make no impression on their retina—a fact of some importance. VOL. VIII. (N.S.) U becomes vastly greater when we cross the "Rubicon" of a certain learned, but unbiological, professor, and strive to form some notion of the world as it appears to the lower animals. Have they the same senses as ourselves? At the first glance the educated public will be disposed to assume that all living beings must as a matter of course be able to see, hear, smell, taste, and feel just as we do, and equally of course must possess no inlet of knowledge to which we are strangers. Closer examination, however, will throw doubts on both members of this proposition. Many animals are blind, not incidentally from disease or accident, but normally, the eyes being sometimes covered over with opaque membranes, sometimes merely rudimentary, and sometimes even totally wanting, the very optic nerve itself being obliterated. Such arrests of development occur inalmost every department of the animal kingdom, even among the mammalia. Two species of mole are not figuratively but absolutely blind, Talpa cæca, found in Southern Europe, and the golden mole of the Cape of Good Hope (Chrysochloris inaurata). A rodent found in the eastern parts of Europe (Spalax typhlus) has eyes so small, so deeply buried in its head, and furnished with so narrow an aperture, that it may be regarded as blind, functionally if not structurally. In the caverns of Kentucky two sightless rats and two bats equally deficient are said to occur, though whether they are totally blind is somewhat doubtful. No blind bird has hitherto been discovered, but amongst amphibians the renowned Proteus anguinus, found in subterranean pools in the caverns of Carinthia, is a signal instance in point. Two blind fishes have also been detected, one of which, Amblyopus cæcus, is peculiar to the Mammoth Cave of Kentucky. The other senses proper to man seem to be shared at least by all the Vertebrata. They possess organs which are the homologues of our own, and which in most cases evidently discharge the same function. One exception on the large scale must not be overlooked. If we consider that smell bears upon substances either themselves aëriform or suspended in air, whilst taste relates to bodies either liquid or capable of solution in liquids, we can scarcely see how smell as differentiated from taste can exist in animals which are always immersed in water, and which respire through gills. With the exceptions thus pointed out, that of blindness in certain species and of scentlessness* in fishes, the We want a word here. The one we use on compulsion might mean not only the inability to perceive odours, but the non-emission of any smell. |