who remembers, as I can, the state of this science half a century ago, must admit that it has made immense progress, and it is now progressing at an ever-increasing rate.
What improvements in medical practice may be directly attributed to physiological research is a question which can be properly discussed only by those physiologists and medical practitioners who have studied the history of their subjects; but, as far as I can learn, the benefits are already great. However this may be, no one, unless he is grossly ignorant of what science has done for mankind, can entertain any doubt of the incalculable benefits which will hereafter be derived from physiology, not only by man, but by the lower animals. Look, for instance, at Pasteur's results in modifying the germs of the most malignant diseases, from which, as it so happens, animals will in the first place receive more relief than man. Let it be remembered how many lives and what a fearful amount of suffering have been saved by the knowledge gained of parasitic worms through the experiments of Virchow and others on living animals. In the future every one will be astonished at the ingratitude shown, at least in England, to these benefactors of mankind. As for myself, permit me to assure you that I honor, and shall always honor, every one who advances the noble science of physiology.
Dear sir, yours faithfully,
| Charles Darwin. |
| To Professor Holmgren. |
Tin in Australia and other Countries.—A German pamphlet by Dr. Eduard Reyer, on "Tin in Australia and Tasmania" (Vienna, 1880), gives some interesting facts relative to the production of tin in different countries outside of Europe. The mining of this metal has become an industry of considerable importance in the Australian colonies. The amount exported from Victoria to England rose from an average of about 130 tons a year between 1860 and 1869, to 2,500 tons in 1877; the production in New South Wales increased from 50 tons in 1872 to 7,000 tons in 1877. Four thousand tons were produced in Queensland in 1874; and the whole amount exported from Australia to England in the first five months of 1877, 1878, and 1879, was respectively 4,300, 4,100, and 2,900 tons. About 4,500 tons were produced in Tasmania in 1877; 4,100 were exported in the first five months of 1878, and 3,300 tons in the corresponding period of 1879. The ore occurs in Australia on the flanks of the mountains which run parallel to the eastern coast, in granite of the Devonian age, and has so far been got by washing from the sediment in the valleys. In Tasmania it is found in the quartz-porphyry of Mount Bischoff, and is likewise obtained by washing. Tin is found in several of the southwestern provinces of China, but it is not so largely produced in that country that considerable quantities arc not imported from abroad; it was formerly sent from Java to England; it was extensively mined in the province of Khorassan in Persia; is mentioned as having been formerly produced in Algeria; and is now produced in the Cape Colony at a rate represented by an exportation of about one hundred tons a year. It is found in small quantities or traces in. several places in the United States, as in Maine, New Hampshire, Connecticut, Pennsylvania, Virginia, North Carolina, Missouri, and California, and in parts of Mexico, but the whole production of North America is hardly worth speaking of. It is, however, a definite article of production and export in some South American states, as Peru, Chili, and Bolivia; it exists in the province of Minas Geraes in Brazil; and several abandoned tin-mines are mentioned in the Spanish West Indies.
The Glacial Ice-Sheet in the Interior States.—Professor N. H. Winchell suggests, in the "American Journal of Science," that the peculiar formation of ice, which Mr. Dall has described as occurring near Behring Strait (see "Popular Science Monthly" for May, page 130), presents features which may formerly have prevailed in our Western and Northwestern States. Both regions are alike free from high land and rocky hills suited for the production of a glacier. The proof that vast fields of glacier-ice formerly existed over our Northern interior States is now rarely questioned; "and it is highly probable," says Professor Winchell, "that the field explored by Mr. Dall is an epitome, under peculiar and somewhat inexplicable circumstances, of the vaster fields which extended from the Rocky Mountains on the West to the Alleghanies on the East, during the latest epoch of continental ice, the only important exception being that over the continent the southern termination of the ice-sheet was everywhere invisible, and abutted nowhere (in the interior) on the
