REVIEWS 509 



interesting and well written. These are complex, transference, repression, 

 conflict, sublimation, and resistance. In spite of paraphrasing, their meaning 

 is yet cryptic and equivocal, although some, such as complex, have come 

 into general use without suspicion of pedantry or arbitrariness. There is a 

 hankering on the part of the authoress for a full discussion of sex curiosity 

 in children, but the present writer's experience can relate more than one 

 case in which irrevocable harm has resulted through suggestions implanted 

 into the child's mind from the libidinous and incestuous thoughts of the 

 analyst. The efforts to understand human motives based upon suspected 

 unconscious tendencies does not set free energy that is said to be used in 

 inhibitions; for it is natural and self-preservative to inhibit and to repress, 

 although too emphatic repression has been regarded as hurtful long before 

 psycho-analysis was taught, for the pedagogic maxim, " Don't say don't," 

 has had a place with teachers long before Freud was known. It is well 

 to warn teachers against the Freudian explanation of wish fulfilments, which 

 this textbook, in common with all the Freudian literature, attributes to the 

 instinct of sex, a view that has become an obsession with this school. 



Robert Armstrong-Jones, M.D. 



Microscopy : The Construction, Theory and Use of the Microscope. By 



Edmund J. Spitta, L.R.C.P., M.R.C.S. [Pp. xxviii + 534, with 83 

 half-tone reproductions from original negatives and 255 text illustra - 

 tions.] (London : John Murray, 1920. Price 255. net.) 



The third edition of Dr. Spitta's work on Microscopy follows in its main 

 features the two previous editions, which have proved of considerable value 

 to workers with the microscope. The book is obviously intended more for 

 the amateur than for the professional microscopist. It is written in an easy, 

 sometimes almost in an unscientific style, but the main purpose in view, to 

 impart to the worker the methods of using the microscope rather than the 

 exact scientific principles involved, is no doubt attained. The opening 

 chapters are devoted to elementary optics, the simple and the compound 

 microscope and to the essential mechanical components of which the latter is 

 built up. A number of instruments by various makers are figured and 

 described. The description is usually laudatory rather than critical, and it 

 is to be regretted that Dr. Spitta has not given the reader the benefit of his 

 knowledge and wide experience in pointing out the defects and shortcomings 

 of some much advertised and consequently much used types of microscopes. 

 The orthodox methods of obtaining what is referred to as a critical image 

 are described, and some illustrations are included among those at the end of 

 the book which are intended to show the characteristics of such an image. 

 There would appear to be no reason why any special term should be introduced 

 to describe a series of simple operations which are essential if a correct image 

 is to be obtained. There are two points of outstanding importance in setting 

 up a microscope, alignment of the axes of the optical systems together with 

 centration of the illuminating beam, and the proper utilisation of the largest 

 possible portion of the aperture of the objective. If these two conditions are 

 satisfied then the resulting image in the microscope will be truthful. The 

 subject of dark-ground illumination is treated somewhat cursorily ; in fact, 

 the impression given is that this method is of little value. It is quite true that 

 its limitations are considerable, but in modern medicine there is hardly any 

 single microscopic process of such practical value. The difference between 

 illumination by transmitted light and objects seen as self-luminous ones — in 

 other words, the fundamental differences between resolution and visibihty in 

 the microscope — is not dealt with satisfactorily, although this is a difference that 

 in practice every microscopist should fully appreciate. 



A fuU description of the usual methods of testing objectives is given, and 



