lOO 



NA TURE 



[May 31. 1894 



to Health," an interesting account is given of •' Caisson 

 Disease" and " Divers' Disease," due to too sudden ex- 

 posure to change of atmospheric pressure, when workinij 

 under deep water, as in the construction of the Forth 

 Bridge. The disease begins with pain and sickness ; 

 paralysis of the lower limbs sets in, and death may occur 

 speedily. A pressure equal to that of four or even six 

 atmospheres is thus sometimes borne, and, if gradually 

 attained, is not necessarily injurious. 



In the "Compressed air bath,'' at the I5rompton 

 Hospital, the pressure rarely exceeds an addition of 

 10 lb. to the square inch, or 3 of an atmosphere. Half 

 an hour is given to reach this pressure, it is maintained 

 for an hour, and half an hour is occupied in reducing it 

 to the natural pressure ; thus all danger of su Iden change 

 is taken away, and it is found that, in asthmatic cases, 

 marked benefit is often secured by the compressed air. 



The value of rarefied air, as at Davos, St. Moritz, or 

 Denver is great ; the analysis of cases thus treated shows 

 an improvement in \ of the cases. 



'• In general results, the English home counties yield 

 the smallest percentage of ' improvement,' and the 

 largest of ' worse.' Next comes the Riviera, not much 

 better ; then, with a rise of 12 per cent, 'improved,' are 

 sea-voyages, the percentage of 'worse' being still large. 

 ' High altitudes' win easily in all categories, with their 

 83 per cent. ' improved," and only 14^ per cent. ' worse.' " 



It must be admitted there is strong evidence in favour of 

 high altitude treatment. The value of such comparisons 

 would be enhanced if we could be certain the patients 

 pursuing different forms of climate treatment conformed 

 to the same rules of hygiene and dietetics. 



The concluding chapter of the book, "On the Higli 

 .Altitudes of Colorado," gives the results of Dr. Theodore 

 Williams' recent visit to Denver, and is thus epitomised : 



"The climate of Colorado is dry and sunny, with 

 bracing and energising qualities, permitting outdoor 

 exercise daily throughout the year. It has rescued 

 many consumptives from a life of invalidism. Its ex- 

 hilarating influence may be traced in the wonderful 

 enterprise which the Colorado people have shown in 

 developing their country. Thirty years ago Denver 

 did not exist; it is now a well-built and well-organised 

 city of 1 50,000 inhabitants." 



This short survey must suffice to show that in the 

 work before us facts are collected and arranged 

 which cannot but prove of essentiar service to the 

 public, and especially to the medical profession seeking 

 the newest information concerning aero-therapeulics. 



OUR BOOK SHELF. 



Hiitories of American Schools for the Deaf, 1817-1893. 

 Edited by Edward Allen Fay, Ph.D. In three volumes 

 Washington, D.C. : the Volta Bureau, 1893.) 



Four hundred years ago the great double-continent of 

 America was discovered, and almost contemporaneous 

 with that event was a second discovery of, perhaps, less 

 apparent but no less real importance. In the fifteenth 

 century Rodolphus Agricola recorded the first instance 

 of a deaf mute who learned to read and write, and not 

 long afterwards Girolamo Cardano, a fellow-countryman 

 of Columbus, insisted that the instruction of individuals 

 thus afflicted was possible though difficult, and, going 

 farther, staled clearly the principle on which such 

 instruction depends. 



NO. 1283. VOL. 50] 



Like many another beneficent discovery, that of 

 Cardano was long in finding recognition, and, although 

 there were isolated cases instructed in Spain, England, 

 Holland, France, and Germany, it was but a century and 

 a half ago that the theory began to be put into practice. 

 Paris claims the merit of giving the first start to the work 

 of benevolence, .\bbe de L'Epee there establishing his 

 school in 1760, similar institutions rising in Dresden and 

 Edinburgh about the same time. From such a beginning 

 has sprung a work which, though carried on for the most 

 part in silence, stands foremost in the philanthropic 

 labours of the world — a work that must have brought 

 light and happiness to many thousands of our less for- 

 tunate brethren, and been the means of developing valu- 

 able intellects which might otherwise have been lost to 

 the community. Some idea of its quiet but steady 

 progress may be gained from the following facts: — In 

 1836 there were 134 schools for the deaf in the world, in 

 1883 there were 397, and in 1893 the number had risen 

 to 435. In the L'nited States fifty years ago there were 

 but six schools, in Canada and Mexico none, while in the 

 three volumes before us are the histories of 79 schools in 

 the United -States, seven in Canada, and one in Mexico, 

 which instruct, respectively, 7,940, 682, and 34 pupils. 



True charity works, as a rule, in the dark ; the outside 

 world knows little as to its achievements, and seems to 

 care as much. Here, however, can be learned something 

 of its labours in one direction and its untiring energy 

 appreciated. We hear little about similar institutions in 

 tills country, although they certainly exist, and a volume 

 compiled on similar lines to the one at present under 

 review would be welcome to all who have to do with deaf 

 persons. This book, prepared for the \'olta Bureau in 

 commemoration of the four-hundredth anniversary of the 

 discovery of America, contains, as we have said, the 

 histories of eighty-seven schools for the deaf and dumb. 

 These histories, which fill three large volumes, were 

 nearly all prepared by the heads of the schools, and, 

 many of them being written by the deaf and dumb them- 

 selves, they form a lasting monument of the excellence 

 of the work done. By the help of excellent portraits and 

 photographs the information to be gained is made ex- 

 haustive, and the reader becomes acquainted not only 

 with the work done, but with the lives of many of the 

 workers, lives which are worthy of a place amonj; those 

 who truly follow in the footsteps of Him who " made the 

 deaf to hear and the dumb to speak." 



P. MACLEOD YEARSLEY. 



Monograph of the Stalactites and Stalagmites of the 

 Cleaves Cove, near Dairy, Ayrshire. By John Smith, 

 Vice-President of the Geological Society of Glasgow. 

 (London : Elliot Stock, 1S94.) 

 The author has taken advantage of the opportunity 

 afforded by the exploration of a cavern in the Lower 

 Carboniferous Limestone, to study the various forms of 

 deposit produced by the percolating waters. He appears, 

 from his preface, to be under the impression that nothing 

 has been previously written on the subject of stal.agmitic 

 deposits, and no references to any earlier literature occur 

 in his pages. This is unfortunate, as a study of the 

 writings of Cohn, and others who have investigated the 

 action of plants in promoting the deposition of calcium 

 carbonate, would have helped him to solve some of the 

 difficulties he has experienced. 



The author classifies the different forms of deposit 

 as " a stalactite " (when it is a pendent icicle-like mass), 

 "a stalagmite" (when a similar mass, rising from the 

 floor), "sheet stalagmite," "wall stalagmite," "tear- 

 bands," "ribs' and " combs," all of which terms explain 

 themselves. He would have done well to consult a 

 botanist before applying the name GallioiicUti to the 

 "confervoid filaments" found in the chalybeate water. 

 The 18 pages of text are illustrated by 36 plates, 



