April i8, 1895] 



NA TURE 



579 



the various baits for the long lines — mussel, scallop, 

 squid, lugworm, whelk, cockle, &c. — mussel is the 

 i most generally distributed, the most easily grown, and 

 altogether the most serviceable and important. The 

 Mussel Commission stated in 1889 that " nearly all the 

 50,000 fishermen of Scotland use mussels as their bait 

 during some part of the year." It has been calculated 

 that the fishing lines used in Scotland in 1893 would, if 

 tied together, nearly encircle the world twice, and 

 probably about 47,000,000 hooks have to be baited (each 

 with two mussels) every time all the lines are set. These 

 statements give some rough idea of the magnitude of the 

 demand for this bait. If squid could be obtained in suffi- 

 cient quantity, it would probably be even more valuable 

 than mussels, but its price is usually prohibitive to most 

 fishermen. .-V fishing firm in Aberdeen paid during this 

 last winter over ^200 for squid bait for a single boat's 

 , lines for the three months October to December, and 

 ! there are fifty to sixty of such boats north of the 

 Tyne. 



One section of this book gives a short account of the 

 anatomy, and the reproduction, and an outline of the 

 development of the mussel. Most of this is very simple ; 

 but it is not easy to understand the following statement 

 (p. 44), where, speaking of the kidneys, Mr. Calderwood 

 says : " Two internal openings also communicate with 

 the cavity in which the heart is situated, and in this way 

 the organ has a more powerful action in aerating the 

 blood " ! Whether " the organ " in question is the heart 

 or the kidney is not very clear, and in either case the 

 statement is equally mysterious. 



As a single female mussel produces two or three 



million young, and as innumerable young mussels all 



round our coast perish miserably every year for want of 



suitable objects to attach to, there can be no reasonable 



doubt that the judicious erection of simple stakes, or 



'' bouchots," would serve a useful purpose, at any rate in 



the collection of seed, even if the further rearing be 



carried on by means of the bed system. The import- 



i ance of transplanting, of cropping the beds by rotation, 



I of exterminating enemies such as starfish and wheiks, 



1 and of avoiding overcrowding, is pointed out ; and we are 



reminded of the opinion of Prof MIntosh, endorsed by 



the Scottish Fishery Board, that " if properly and wisely 



I managed, a mussel fishery will rapidly repay the small 



I initial expense, and might, indeed, be made largely 



profitable." 



The book concludes with a chapter on the legal aspects 



i of the matter, extracts from the Acts in regard to mussel 



fisheries, and information on the methods of obtaining 



'fishery "orders" in England, Scotland, and Ireland. 



Some of these legal processes seem unnecessarily com- 



j plicated and expensive, and it is certainly unfortunate 



[ that our local fishery committees can make regulations 



I in regard to their mussel beds, but cannot improve 



I them by cultivation ; and yet in parts of England the 



I mussel is even more important than in Scotland, as it is 



( used not merely as bait, but very largely as food in some 



districts. The book seems singularly free from typo- 



! graphical errors — a curious slip on p. 1 1 suggests that 



the author's mind was so full of his subject that he has 



mis-spelled Mr. Bateson's name. W, A. H. 



NO. 1329, VOL 51] 



HISTORICAL EPIDEMIOLOGY. 

 A History of Epidemics in Brilain. By Charles 



From the Extinction 

 Time. (Cambridge : 



Creighton, M.A., M.D. Vol. ii. 

 of the Plague to the Present 

 I University Press, 1894.) 



THE first volume of this work was reviewed in these 

 columns about three years ago, and Dr. Creighton 

 has now brought his difficult task to completion. The 

 labour of disinterring the facts of epidemiological 

 history from the scattered chronicles in which they 

 lie hidden is very considerable, and, when this is 

 accomplished, the historian is further confronted with 

 the difficulty of identifying, under the confused nomen- 

 clature of by-gone days, the various pestilences described, 

 and of assigning to them their proper place in modern 

 nosology. 



Dr. Creighton has undoubtedly earned the thanks of all 

 students of epidemiology for the painstaking and laborious 

 compilation of facts and references which he has brought 

 together in the present volume. The magnitude of the 

 labour has been immense — the more so since, as the 

 author remarks in the preface, he has had little help from 

 predecessors in the same field. He has at times in- 

 corporated with the strictly historical portions of the 

 work aetiological considerations which, we fear, will 

 hardly commend themselves as of equal merit with the 

 rest ; these, however, form but a small part of the whole, 



j and though they call for comment, should not be allowed 

 to interfere with our appreciation of the value of the 



'■ book. 



The opening chapter deals with typhus and other con- 

 tinued fevers, and its historical interest is very great. It 



, well illustrates the close connection which exists between 



' the epidemic prevalence of this group of diseases, and 

 the physical environment and social conditions of the 

 population, nor could an instructive lesson in hygiene 

 have been better presented. It is interesting, too, to 

 trace the gradual rise of more exact pathological 

 notions, whereby the old medley of spotted, putrid, 

 miliary, and comatose fevers has been resolved into our 

 modern typhus, enteric, and relapsing fevers. The 

 grouping together of influenzas and " epidemic agues " 

 in another chapter seems warranted by the etymology of 

 the term ague (Latin : acutus), the expression being used 



I in early times for any sharp fever : the term "influenza" 



' did not reach England till 1743. 



I Small-pox naturally receives a full measure of attention. 

 The statements put forward to show that during the 

 seventeenth century the mortality from this disease had 

 not that excessive incidence on infants which afterwards 

 became the rule, are not, in the necessary absence of any 

 statistical evidence, sufficiently convincing. The history 

 and practice of inoculation are treated of at great length, 

 and the account is full of interest. Dr. Creighton's 

 opinions on the subject of vaccination are well known, 

 and it is a pity that in a purely historical work, any bias 

 should have been allowed to appear. He has perhaps 

 done his be5t to avoid it by treating vaccination, after 

 the year 1825, as "^r //y/t^/Zic'jv irrelevant," though this 

 proceeding may raise a smile on the faces of many of his 

 readers. Even in the preface the assumption that variola 



