5o6 SCIENCE PROGRESS 



committee and a method for making a rough estimate of costs : next, three 

 chapters devoted to the special requirements of chemistry, physics and 

 biology (including geology) : then a chapter treating in some detail of 

 laboratory services, such as gas, water, electricity, ventilation and drainage : 

 and finally a set of detailed drawings of recent designs, both for schools and 

 technical colleges at home and abroad. The style is restrained and undogmatic ; 

 it is perhaps too quiet. A few examples of bad design, with a critical 

 commentary, might have added to the value. For example, it is pointed out 

 quite casually (p. 9) that the laboratory and not the lecture theatre should 

 be placed on the noisy side of the building, an obvious fact, indeed ; but 

 the reviewer has had a good deal of experience in lecturing to the strains of 

 a barrel organ, and, consequently, feels that the matter might be put more 

 strongly — the opportunity was provided by a certain design shown in the 

 last chapter of the book. 



So many neat ideas are brought to the reader's notice that to select two 

 or three for special reference here is almost unfair to the author. We may, 

 however, perhaps be permitted to draw attention to the lecture table " foot- 

 lights " used in Prof. Kent's physiological theatre at Bristol, to the use of 

 aniline black covered with a lead paint as a protection for the tops of 

 ordinary pine-wood tables in certain schools in America, and to the V-shaped 

 tables for the use of classes requiring microscopes, described by Sir Arthur 

 Shipley in his witty introduction. 



The book should find a place in the library of every growing institution, 

 and should earn for its author the very sincere gratitude of all those who have 

 ■occasion to make practical use of its contents. The reproduction of plans, 

 printing, and general get-up of the work are excellent, and it has a sufiicient 

 index. 



Critical Microscopy. By Alfred C. Coles, M.D., D.Sc, M.R.C.P., F.R.S., 

 (Pp. viii + 100, with 8 illustrations.) (London : J. and A. Churchill, 

 1921. Price 7s. 6d. net.) 



The author regards this book as a supplement to, rather than a substitute 

 for, the standard works on the subject already in existence. From this 

 standpoint it is possible to justify the production of such a work ; otherwise 

 it would be difficult, as there is little effort to explain even the elementary 

 principles of microscopy. The book consists in large part of abstracts from 

 published papers or personal communications from Mr. E. M. Nelson, to 

 whom the well-known term " Critical Microscopy " is due. 



The first part consists of a description of the Microscope and its Acces- 

 sories. Then follows a section on Manipulation, such subjects as the adjust- 

 ment of the sub-stage condenser, and dark-ground illumination rightly 

 receiving a full share of attention. The selection of suitable objectives for 

 bacteriology or pathology — and these branches are particularly, in fact 

 almost exclusively, referred to in the book — is well treated. The author 

 insists on the great advantage of using such a lens as an 8 mm. apochromatic 

 for medium power work. He sets out in detail the features of such a lens, 

 and mentions that for dark-ground work it will do all that is necessary, even 

 in the identification of such objects as malarial parasites in blood films, a 

 claim that is fully justified. Strong objection is taken to the use of objective 

 changers in place of the more common, but less efiicient, triple nose-piece. 

 The only conclusion to be drawn is that this opinion has been formed without 

 any, or sufficient, experience, as there is no comparison between the two 

 appliances for accurate work. Preference is also given, even to the exclusion 

 of all other light sources, to a paraffin lamp. Again, it can only be concluded 

 that sufficiently exhaustive efiEorts have not been made with other illuminants. 



