lOO 



NA TURE 



[June 3, 1897 



developing organisms, like adults, are possessed of con- 

 siderable powers of adaptability. Exposed, for the most 

 part, to very similar conditions, they develop in a very 

 similar way, which we come to recognise as the normal 

 way. But, if the conditions are varied within certain 

 limits, the developing organism adapts itself to those 

 changes, and completes the cycle of its existence. All 

 the evidence, whether from the side of Roux, or from that 

 of Hertwig, Driesch and others of the same opinions, shows 

 that there is a very definite limit to the disturbances to 

 which the developing ovum is capable of adapting itself. 

 Such discussions as are contained in this book only serve 

 to bring forward more prominently the view that the 

 organism is the result of the interaction between its 

 own specific nature and the environment. It would 

 seem that the next essential step in biological inquiry 

 is to determine in special instances what is the nature of 

 the reaction of living substance to external conditions. 

 Much has been attempted in this direction, but the results 

 have hitherto been indefinite, and even contradictory. 



THE EXAMINATION OF THE BLOOD IN 

 DISEASE. 

 A Guide to the Clinical Examination of the Blood for 

 Diagnostic Purposes. By Richard C. Cabot, M.D. 

 With coloured plates and engravings. Pp. xix + 405. 

 (London, New York, and Bombay : Longmans, Green, 

 and Co., 1897.) 



SINCE Hughes Bennett's observations on leuco- 

 cythemia were recorded, great advances have been 

 made in the methods of examining blood, and a certain 

 limited number of physicians, appreciating the importance 

 of the changes that take place in the blood as indicative 

 of changes in the more fixed tissues, have laid considerable 

 stress on the necessity of determining the exact constitu- 

 tion of the blood in certain forms of disease. With all 

 this, however, the use of the various apparatus devised 

 for such estimations have never come into general use. 

 For this there appear to have been two principal 

 reasons: (i) that the medical man has not considered 

 that the information to be derived from such examination 

 is at all commensurate with the time and skill required 

 to obtain such information ; (2) the second reason, which, 

 however, is intimately bound up with the first, is that 

 hitherto we, in this country at any rate, have been be- 

 holden for any systematic account of the pathology and 

 clinical pathology of the blood to Hayem in France, 

 and to Grawitz, Schmaltz and Rieder in Germany, as up 

 to the present there has been no systematic treatise in 

 the English language on the clinical examination of the 

 blood. Indeed, in recent years, although much valuable 

 work on the blood of animals artificially treated has 

 been published by a number of our younger physiologists 

 and pathologists, and although Gower's work has formed 

 the basis of much of the clinical examination that has 

 been done, it is to the impetus that Metchnikoff and 

 Ehrlich have given to the study of the blood as a his- 

 tological tissue that these advances have been made. 

 h. similar impulse seems to have been given in America 

 with the result that there has come from the Johns 

 Hopkins Laboratories a work which, whilst based on the 

 researches carried out in France and Germany, has 

 NO. 1440, VOL. 56 



nevertheless a certain individuality and value quite apart 

 from that reflected in it from foreign workers. Dr. 

 Cabot, approaching the subject from the point of view 

 of a man who has made himself thoroughly familiar 

 with the various methods of examining blood, having 

 already examined the blood from nearly a thousand 

 cases, and has at his command the observations on 

 about three thousand more cases examined in the 

 Massachusetts Hospital, gives an account of the structure 

 of the blood, in which, however, it is evident that 

 Ehrlich's observations have been made the basis of the 

 descriptions, as outside Ehrlich's classification the ac- 

 counts of the structure and appearance of the corpuscles 

 are somewhat meagre, especially from the purely clinical 

 point of view. In the accounts of the systematic work 

 this is, perhaps, not altogether a disadvantage ; still we 

 think that those who come to compare this work with 

 the results that they may obtain, either in clinical or 

 in experimental work, will find that full use has not been 

 made of more recent investigations, especially those that 

 have been carried on in this country. 



It is impossible, in a short review, to give more than 

 a very meagre outline of this work ; but, as it is really 

 the first of its kind that has appeared in the English 

 language, it may be well to indicate the enormous amount 

 of matter that has been collected and arranged in handy 

 form for reference. In the first instance, the methods of 

 clinical examination of the blood are set forth, and from 

 the completeness and accuracy of the descriptions given, 

 and from the fact that the author is so frequently able to 

 indicate the difficulties met with, and the methods of 

 getting over them, it is evident that he has a thorough 

 practical acquaintance with his work. We are glad to see 

 that he insists very strongly upon the examination of the 

 fresh blood — a method of examination which is far too 

 little used in these investigations. The instruments re- 

 commended are all of German origin, and the difficulty 

 that has hitherto been found by those working with these 

 instruments are acknowledged. What strikes one very 

 forcibly in this connection is the value of the " Tinto- 

 meter" system as compared with any of those here men- 

 tioned. In describing the myelocytes— the non-motile 

 marrow cells with their large, simple nuclei — Dr. Cabot 

 appears to assign to mere mechanical conditions the 

 regularity of the nucleus, and he says that " the absence 

 of amoeboid motion, and of journeys through tissues, 

 leaves the nucleus evenly and moderately stainable 

 throughout, while the amceboid blood leucocyte, through 

 the wear and tear of its migrations, gets its chromatin 

 irregularly distributed, condensed here, pulled out thin 

 there, and hence stains unevenly or is mottled." This 

 point is referred to on several occasions throughout the 

 book. Surely the want of amceboid motion is indicative 

 of the inactivity of the cell, the regularity of the nucleus 

 pointing to the fact that it is in the so-called resting-stage, 

 especially as it is indicated that marked degenerative 

 changes may be observed in these myelocytes. We should 

 feel strongly inclined to reverse Dr. Cabot's cause and 

 effect. After an account of the methods of clinical 

 examination and the physiology of the blood, several 

 chapters are devoted to the general pathology of the 

 blood, after which the bulk of the book is devoted to the 

 special pathology of the blood, primary anaemias, leuk- 



