286 



THE POPULAR SCIENCE MONTHLY. 



potentially represents a trough. The water 

 from the edges of this trough flows back 

 obliquely toward the middle, and by the 

 time it reaches the middle it gains such 

 momentum that the middle of the stream is 

 made the highest. Every stream is by 

 these forces resolved into two cylinders, re- 

 volving spirally on parallel axes in opposite 

 directions that is, outward at the bottom, 

 upward at the edges, inward at the top, and 

 downward through the middle. The prin- 

 ciple is denominated " the law of the double 

 spiral," and affords an explanation of all 

 the phenomena in question. Since glaciers 

 are subject to the same conditions, it is be- 

 lieved that they are subject to the same 

 movements. It is believed to apply to air 

 currents also, and that the Western blizzard 

 and the Texas norther may be in part due to 

 waves of cold air descending to take the 

 place of that which friction has caused to 

 ascend the Rocky Mountains. 



Diffusion of Jade. Inferences that ex- 

 tensive intercourse between distant regions 

 prevailed in prehistoric times have been 

 drawn from the general dispersion of jade 

 ornaments in the monuments all over the 

 world, and the paucity of known sources of 

 the mineral. Many possible sources of jade 

 have, however, been discovered within a 

 few years, in view of which the necessity of 

 men anywhere having to go to the ends of 

 the earth for their treasure becomes less ap- 

 parent. Mr. F. W. Rudlcr recently mentioned 

 to the Anthropological Institute, as among 

 the later discoveries of jade in situ, those of 

 Herr Taube, of Breslau, at Jordans Miihe in 

 Silesia, and at Reiehenstein ; the rough peb- 

 bles that have been found in the valleys of 

 the Sann and the Mur in Styria; Dr. Daw- 

 son's account of the occurrence of bowlders 

 partly sawn through on the Fraser River ; 

 and the discovery by Lieutenant Stoney of 

 the mineral in situ at the Jade Mountains, 

 north of the Konak River, in Alaska. 



Medicine in Thibet. The course of in- 

 struction at the Thibetan University of the 

 Guinoie Ozero Monastery is very elaborate 

 and is adjusted for ten years of studentship. 

 It includes the Thibetan and Mongolian lan- 

 guages, religion, drawing, handicrafts, astron- 

 omy, astrology, philosophy, and theology. 



The medical course requires three years. 

 The Thibetan medical authorities, according 

 to the Russian M. Ptitsyn, recognize 101 

 fundamental diseases ; and 429 names of 

 elements of drugs used by them are given. 

 Of the 101 diseases, only two (paralysis and 

 a kind of influence of the planets) are at- 

 tributed to a mythical origin ; and of the 

 429 drugs, only three (the bones of a dragon, 

 the horns and the skin of the unicorn) have 

 a similar derivation. The remainder of the 

 drugs are chiefly herbs, seeds, fruits, roots, 

 and flowers, and partly mineral matters. 

 All, except quinine, which is bought in Rus- 

 sia, are obtained in Chinese drug-shops. 

 M. Ptitsyn visited one of the drug-shops, 

 and found all drugs kept in order in separate 

 drawers. He has brought samples of 202 

 drugs to St. Petersburg, and they will be 

 analyzed by the Medical Academy. 



NOTES. 



The fourth season of the Marine Biologi- 

 cal Laboratory at Wood's Holl, Mass., Dr. C. 

 0. Whitman, director, will open for teachers 

 and students, with courses of seven weeks' 

 instruction in zoology, botany, and micro- 

 scopical technique, July 8th. The first week 

 will be devoted to the study of the lobster, 

 the second to annelids, the third to coelen- 

 terates, the fourth to mollusks, the fifth to 

 echinoderms, the sixth to crustaceans, and 

 the seventh to vertebrates (marine). The 

 laboratory for investigators will be open 

 from June 1st to August 20th, furnished 

 with aquaria, glassware, reagents, etc., but 

 not with microscopes and microtomes. 



M. dk Quatrefages lately reported to the 

 French Academy of Science the discovery, 

 by M. Wanzel, of the skull of a cave bear 

 bearing the marks of a wound that had been 

 received from a stone hatchet. The wound 

 had healed, with the formation of a callus. 

 Two pieces of the hatchet had been broken 

 off by the blow, one of which was left in 

 the wound and had been covered by the 

 callus. 



The Pope has written a letter announc- 

 ing the re-establishment of the donation for 

 the astronomical observatory at the Vatican. 

 He declares that he is solicitous for the 

 progress of science, and places the observa- 

 tory in the same rank with other papal in- 

 stitutions. 



The seventieth birthday of Prof. Helm- 

 holtz will occur in August next, and, in'antici- 

 pation of the event, Profs. Virchow and Du 



