50 



NATURE 



[Mav 1 6, 189: 



as aflfectcd by moisture, where the author computes and 

 illustrates the amount of heat abstracted from the body 

 in order to con\crt into vapour the water which a 

 saturated suit of clothes is capable of containing. 



This latter remark has reference naturally to the 

 chapter on Precipitation, which, with the following one 

 on Thunder-storms, does not call for any special remark. 

 Emphasis is laid on the purifying influences that rain and 

 snow have on the atmosphere ; but little is said, perhaps, 

 because little is known with certainty, of cleansing in- 

 fluences on water. The question how far water once con- 

 taminated can be restored to its ori^'inal organic impurity, 

 without the processes of evaporation and reprecipitation, 

 has exercised the minds of chemists and sanitarians in 

 this countr)' with some severity. Information is still neces- 

 sary- both as to the processes at work and the agents by 

 which impurities are removed, as they admittedly are, by 

 some self-cleansing method. The author is understood 

 to recommend filtration as especially necessaiy to elim- 

 inate (iius:usc/ifidc-n) bacteria, presumably bacteria of a 

 pathogenic character. He does not seem to recognise 

 the fact, if it be a fact, that a filter-bed covered with bac- 

 teria has still the power of arresting in a ver)- consider- 

 able degree the bacteria in the water that fillers through 

 it. How this is accomplished is another matter, which 

 may not concern meteorology, but the large questions of 

 sedimentation and percolation of water in its passage 

 through the ground comes naturally into the treatment by 

 Dr. Bebber, more especially as he enters with some 

 degree of detail into ground water, and the conditions 

 which make it potable or otherwise. 



Wind and the motion of cyclones are subjects that the 

 author has made peculiarly his own, and are dealt with 

 here at considerable length. Considering the important 

 results that follow the transport of masses of air from 

 place to place, and the mingling and purification of the 

 atmosphere that is thus effected, it is not suggested that 

 the subject receives an undue amount of .attention. The 

 connection between cyclonic paths {Ziigstrassc) and 

 hygiene, however, is not so immediately evident; but the 

 subject is one that has long interested Dr. Bebber, and 

 he naturally has much to say. It is meteorology- pure 

 and simple, and has this defect, that it is scarcely full 

 enough for the student of that science, and in too great 

 detail for the sanitarian. 



Perhaps the most interesting chapter in the book is the 

 last, on Climate, and in which is treated diseases under 

 various climatic conditions. On page 275 is given a table 

 showing the annual mortality per thousand in various 

 parts of the world. This table is apparently thrown 

 together haphazard, and does not exhibit that careful 

 arrangement by which Dr. Bebber in other parts of his 

 book has illuminated his work and instructed ihc student. 

 But the bald facts, as written down, gain by that veiy 

 absence of symmetry, and are both interesting and 

 gratifying. It is true, as the author is careful to point 

 out, that the facts have been gathered under very various 

 circumstances, under various authorities and systems, 

 and arc not strictly comparable ; but making every allow- 

 ance for inexact compilation, they do exhibit a manifest 

 improvement in the health of nations, and bear a gratify- 

 ing testimony to the successful study and practical 

 enforcement of sanitary laws. The few samples we can 

 NO. 1333. vol. ;:.l 



I extract illustrate best the increased adaptibility of 

 individuals to meet those conditions that are generally 

 regarded as adverse to health and longevity. Take the 

 case of British troops in India : 



From 1800-1830. .\nnual de.-ith r.ite per thousand ... 84 6 



„ 1S30-1856. „ 577 



„ 1869-187S. ,, 19-3 



,. 1S79-1SS7. .. 16-3 



From the West Indies the evidence is of the same 

 character : 



From 1820-1836. EuropeanjTroops, Jamaica, Moilaliiv 121 

 „ 1817-1846. ,, ,, West Indies ,. 75 



,, 1879- 18S7. ,, ,, Jamaica ., ii'o 



,, 1820-1S36. Negro Troops, Jamaica ., 30-0 



„ 1879-18S7. „ „ „ „ 11-6 



On the Gold Coast, the figures are so remarkable that 

 that they can only be explained by supposing some 

 different method of computation to have been employed 

 in the two circumstances : 



From 1829-1836. European Troops, Gold Coiist ... 4S3 ! ! 

 ,, 1S79-1885. ,, ,. .. ... 68 



Possibly a similar source of error will explain the only 

 retrograde case to be met with, for which the insalubrious 

 climate of Cayenne is responsible : 



From 1819- 

 In 1855 



849. Troops, Mortality 



27-2 

 90-8 



Of course some of these beiieticent results may be 

 attributed to greater care in the selection of men to be 

 sent to these regions ; but it would be distinctly wrong to 

 deny also that much is due to insistence on improved 

 conditions of residence, of clothing, of food and drink, 

 especially in the maintenance of uncontaminated sources 

 of drinking water, in fact an insistence on those conditions 

 which sanitary science has shown to be of the utmost 

 importance to individuals and nations. 



Possibly, enough has been said here to show that we 

 have to do with a veiy interesting book, and one far reach- 

 ing in its aims. If we have to inakc any complaint, it is 

 only to express the regret that it is not more so. It is the 

 omissions that are sometimes disappointing, the contents 

 never arc. We give, in conclusion, one last illustration. 

 Remembering that the book is issued from Hamburg, and 

 that this town suffered severely from the scourge of 

 cholera in 1892, one cannot but feel that the Observ- 

 atory is in possession of facts which could not but be of 

 interest in discussing the vexed question of the spread of 

 this disease. Beyond the slightest possible mention on 

 p. 287, the author does not refer to it. Yet it is suggested 

 that he could have told us authoritatively what meteor- 

 ological conditions coincided with the greatest spread of 

 the disease, that he could have given us details of the 

 temperature of the ground and of the Elbe water (see 

 p. 147) that presumably favoured the increase of the 

 bacillus, if it did not come within his province to discuss 

 any differences of morphology, of virulence, or repro- 

 ductive faculty in the vibrio. 





