November 15, 191 7] 



NATURE 



207, 



The volume is divided into three parts. About 

 a third of its bulk deals, first, with anatomy and 

 physiology, and, secondly, with the factors which 

 determine the departure of the thyroid and para- 

 thyroid g-lands from the normal. The remaining- 

 two-thirds of the volume are devoted to a con- 

 sideration of the diseases of the thyro-parathyroid 

 g-lands. 



The anatomy and histology of the glands are 

 admirably described, and in no other work can one 

 find so concise and accurate an account of the 

 i histological alterations presented by the thyroid 

 I in its various degrees of physiological activity. 

 j The physiology of the glands, despite the large 

 amount of recent work upon them, is still obscure, 

 and some of the functions ascribed to them by the 

 author do not carry conviction. His statement 

 that " the thyroid gland is to the human body what 

 the draught is to the fire " is a particularly happy 

 one. Further than that it is, perhaps, unsafe to 

 go. The thyroid stimulates metabolism in 

 general, and the growth of certain organs in 

 particular. Hence it follows that secondary re- 

 sults occur in the body from the increased activity 

 of the stimulated organs. There is evidence, in- 

 deed, that the thyroid is closely co-ordinated with 

 other ductless glands, and that pathological altera- 

 tions in its activity upset the normal balance be- 

 tween them. There are also sex differences as 

 yet imperfectly understood. Excess of thyroid, 

 for example, checks the development of the pitui- 

 tary body in the female, but accelerates it in the 

 male. Further differences in the sexes result from 

 this peculiarity. 



Major McCarrison insists upon the great im- 

 portance of the thyroid in maintaining the health 

 and efficiency of the body at different stages of the 

 life-history of the individual, and shows how its 

 activities are normally influenced. Some of his 

 statements cannot escape criticism. That "mar- 

 ried men under forty years of age are, on the 

 whole, • of better physique than the unmarried" 

 may be true enough, but that this is " a fact which 

 is probably dependent in considerable measure 

 on the maintenance of thyroidal activity which 

 marriage ensures " is an assumption that it would 

 take much evidence to prove. 



The factors which bring about pathological 

 changes in the thyroid Major McCarrison dis- 

 cusses in detail, and this is one of the most valu- 

 able sections in the book. The author divides 

 them into three categories — nutritional, infectious, 

 and psychic. Major McCarrison has established 

 beyond doubt that endemic goitre is frequently the 

 result of infection of the alimentary canal by the 

 fcccal contamination of drinking water. The 

 exact organism or organisms responsible have not 

 1>cen isolated, and, indeed. Major McCarrison's 

 observations leave one somewhat confused as to 

 whether the virus is the product of a special 

 organism or of the normal bacteriological flora of 

 the colon. Predisposing factors are of some im- 

 jxirtance, and their nature is fully considered. In 

 spite of the strong evidence brought forward, one 

 is not quite convinced that Major McCarrison has 

 NO. 2507, VOL. 100] 



altogether solved the problem of the causation of 

 endemic goitre. Does the condition occur in all 

 districts where the drinking water is thus con- 

 taminated? These must be fairly numerous. On 

 the other hand, goitre may be very prevalent, as 

 it is in a district in New Zealand, where the water 

 supply is entirely derived from deep artesian wells, 

 the water from which is stated to be bacteriologi- 

 cally pure. In that district radium emanations in 

 the water are generally blamed. 



The major portion of the volume is an excellent 

 work on the diseases of the thyroids and para- 

 thyroids, and as such is a valuable addition to 

 medical literature. Of its many admirable fea- 

 tures, that of the treatment of these conditions de- 

 serves especial mention. As is to be expected 

 from the views of the author, the promotion of a 

 healthy intestinal condition is of paramount im- 

 portance in treatment. The author lays stress on 

 the frequency with which Graves's disease is asso- 

 ciated with, and presumably caused by, intestinal 

 disorders. He regards the increased activity of 

 the thyroid as a result of toxaemia, and until this 

 is remedied treatment based on diminishing the 

 secretion by medical or surgical means is ob- 

 viously misapplied. 



The volume is full of interesting information, 

 and will be welcomed by physiologists and medical 

 men generally. P. T. Herring. 



OUR BOOKSHELF. 

 The Use of the Voice. By the Rev. T. Grigg- 



Smith. Pp. 118. (London: S.P.C.K., 1917.) 



Price 25. 6d. net. 

 This is an admirable little book written by a 

 teacher of experience who realises the importance 

 of careful training in the use of the voice both in 

 singing and in reading. The mechanism of the 

 larynx is described in simple and, so far as pos- 

 sible, in untechnical language, and there is a suc- 

 sinct account of the mechanism of breathing. 

 The author favours the view that the kind of 

 breathing best adapted for the development of a 

 good voice is neither wholly diaphragmatic nor 

 wholly higher costal, but what may be termed 

 general breathing; in other words, all parts of 

 the mechanism of the chest should be brought into 

 play. Very sensible instructions are given as to 

 the use of the resonance cavities on which the 

 quality of the voice largely depends. Graduated 

 exercises on vowel and consonant sounds are 

 highly recommended, and there can be no doubt 

 that, following the good advice given, the best 

 use can be made of the pupil's structures for voice 

 production. We accept the author's view that 

 far too little attention is paid to the education 

 of the voice both in ordinary conversation and in 

 public speaking, and that we have, therefore, 

 often to suffer from mumbling, indistinct utter- 

 ance, lack of modulation, and incorrect accentua- 

 tion. Not only should one be trained to express 

 his thoughts when "on his feet," but he should 

 also be able to express them in sounds that give 

 pleasure to those who listen. How very often is 



