POPULAR MISCELLANY. 



425 



who remembers, as I can, the state of this sci- 

 ence half a century ago, must admit that it lias 

 made immense progress, and it is now progress- 

 ing at an ever-iucreasing rate. 



What improvements in medical practice 

 may be directly attributed to physiological re- 

 search is a question which can be properly dis- 

 cussed 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 suflfering have been saved by the 

 knowledge gained of parasitic worms through 

 the experiments of Virchow and others on liv- 

 ing animals. In the future every one will be 

 astonished at the ingratitude shown, at least in 

 England, to these benefjictors 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 Anstralia and other Conntries. 



A German pamphlet by Dr. Eduard Reyer, 

 on " Tin in Australia and Tasmania " (Vi- 

 enna, 1880), gives some interesting facts rel- 

 ative 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 Vic- 

 toria to England rose from an average of 

 about 130 tons a year between 1860 and 

 1869, to 2,500 tons in 18*77 ; the produc- 

 tion in Xew 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 re- 

 spectively 4,300, 4,100, and 2,900 tons. 

 About 4,500 tons were produced in Tasma- 

 nia 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 wash- 

 ing. Tin is found in several of the south- 

 western provinces of China, but it is not so 

 largely produced in that country that con- 

 siderable 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 men- 

 tioned as having been formerly produced 

 in Algeria; and is now produced in the 

 Cape Colony at a rate represented by an ex- 

 portation 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, Penn- 

 sylvania, Virginia, Xorth 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. 



Tlie Glacial Ice-Sheet in the Interior 

 States. Professor N. H. Winchell sug- 

 gests, in the " American Journal of Sci- 

 ence," 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 pre- 

 vailed 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 prob- 

 able," says Professor Winchell, "that the 

 field explored by Mr. Dall is an epitome, 

 under peculiar and somewhat inexplicable 

 circumstances, of the vaster fields which ex- 

 tended from the Rocky Mountains on the 

 West to the Alleghanies on the East, dur- 

 ing 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 



