POPULAR MISCELLANY. 



711 



are gold and silver, which are found in 

 minute quantities, Iceland-spar, pure spe- 

 cimens of which are valued for optical in- 

 struments and cabinets, coarse chalcedonies 

 and zeolites, lignite, basalt, and volcanic 

 products. The manufacturing industry of 

 the country is confined to woolen fabrics, 

 socks and stockings, gloves, and a home- 

 spun cloth, which are excellent. 



The Eyesight of Readers. A writer in 

 the " Library Journal " calls attention to 

 the danger which readers run of injuring 

 their eyesight by the use of a bad light. 

 He remarks that engravers, watchmakers, 

 and all others who use the eyes constantly 

 in their work, take extra care to preserve 

 them by getting the best possible light by 

 day, and using the best artificial light at 

 night. The great army of readers are care 

 less, and have, sooner or later, to pay the 

 penalty of their carelessness by giving up 

 night-work entirely, and sometimes read- 

 ing, except at short intervals and under 

 the best conditions. All departures from 

 common type, making the matter more dif- 

 ficult for the eye to take in, increase the 

 danger. The magnitude of the physical 

 labor of reading is not appreciated. A 

 book of five hundred pages, forty lines to 

 the page and fifty letters to the line, con- 

 tains a million letters, all of which the eye 

 has to take in, identify, and combine each 

 with its neighbor. Yet many readers will 

 go through such a book in a day. The task 

 is one he would shrink from if he should 

 stop to measure it beforehand. The best 

 positions and best lights, clear type, plain 

 inks, with the best paper of yellowish 

 tints, and abundant space between the lines, 

 afford the best safeguards against harm. 



What Vivisection has done for Man. 



Dr. Charles Richet, in a vigorous defense of 

 the practice of vivisection, demands that it 

 shall be judged by its practical results, and 

 claims that, if it can be shown that we have 

 gained by that method of experiment the 

 means of curing one or two diseases of man 

 or of assuaging pain, it must be considered 

 lawful. He cites a number of discoveries 

 that have been made through vivisection to 

 sustain his position. Among them is the 

 discovery of the circulation of the blood. 



Galen established the fact that the arteries 

 contained blood by observations in the ar- 

 tery of a living animal ; Harvey opened the 

 chests of living animals, cut into the peri- 

 cardium, observed the contraction of the 

 heart, and what was going on in the veins 

 and arteries, and deduced from what he saw 

 his theory of the circulation. Transfusion 

 of blood, an operation resorted to in ex- 

 treme cases with the best results in saving 

 life, was introduced after its possibility had 

 been ascertained from experiments upon ani- 

 mals first made in 1664 by Lower and after- 

 ward by Denis. " Experiment alone," Dr. 

 Richet says, " will teach us precisely what 

 quantity cf blood is necessary and what is 

 harmful; and if over-sensitiveness forbids 

 animal suffering for this end, then the ex- 

 periments would have to be made on human 

 beings." The mode of death from the inha- 

 lation of carbonic oxide, and, correlatively, 

 the method of avoiding or preventing death 

 from inhalation, have been made known 

 only through vivisection. So also " all that 

 we know in hygiene of the quantity of air 

 necessary to support life is the result of ex- 

 periments on dogs and rabbits. Sometimes 

 a precise knowledge of the conditions of 

 respiration has served to prevent men from 

 perishing." Only two methods exist by 

 which we may learn the conditions of gastric 

 digestion and collect its secretion, viz., by 

 observation of gastric fistula? produced by 

 chance in man, and by artificial fistulas in 

 animals. The first method has been pos- 

 sible only in three or four instances, but the 

 effect of food on the gastric secretion in 

 dogs and cats has been largely observed ; 

 and the knowledge of the remedies which 

 have been applied to the relief of dyspepsia 

 has been derived from such studies.' Our 

 knowledge of nutrition has been largely 

 added to by means of experiments in which 

 dogs and cats have been submitted to varied 

 alimentation, and from which the quantity 

 and quality of food necessary to sustain life 

 have been deduced. What we know of the 

 nerves has been gained from studies of ani- 

 mals, as have also the means of relieving 

 neuralgias and paralysis, in which, thanks 

 to the scientific analyses of the vivisectors 

 Fritsche, Hitzig, and Ferrier, " we can pass 

 from the effect to the cause, and assign to 

 paralysis a central lesion at a well-deter- 



