January 19, 1905] 



NA TURE 



269 



The book is provided with a large number of blocks 

 in the text, nearly all maps, in which, with very few 

 exceptions, but one method of representing relief is 

 adopted — that of shaded areas bounded by contour 

 lines. The method is valuable for some purposes, but 

 as a means of representing the form of the ground is, 

 in most cases, inferior to the much abused " cater- 

 pillar " method of delineation, and frequently conveys 

 a misleading impression. The figure intended to re- 

 present the lower Brahmaputra valley and Gangetic 

 delta is an instance of this, while that intended to 

 represent the orography of the Hindu Kush looks more 

 like an ink-maker's advertisement. In the coloured 

 maps the complete absence of hill shading gives to 

 the Thibetan plateau an air of flatness which it is 

 far from possessing in reality, yet it would be unfair 

 to conclude this notice without a word in their praise. 

 Mr. Bartholomew has accustomed us to a high 

 standard of workmanship, but his map of India, re- 

 produced in this book, has seldom been equalled for 

 intricacy and accuracy of colour printing, and for 

 success in showing the leading features of the relief 

 of the land. 



PHYSICAL AND PHYSIOLOGICAL ASPECTS 

 OF LIGHT. 



Light Energy; its Pliysics, Physiological Action, and 

 Therapeutics. By Margaret A. Cleaves, M.D. Pp. 

 xiv + 827. (London: Rebman, Ltd., 1904.) Price 

 21s. net. 



WHILE this book is written primarily to further 

 our knowledge of the properties and uses of 

 that form of energy called light, in the treatment of 

 disease, yet it will be found of great interest to those 

 whose study is mainly confined to the purely physical 

 aspects of light phenomena. The subject is treated 

 from the modern view of energy in the form of waves 

 of a certain length and direction, but at the same time 

 the emission theory is not entirely ignored on account 

 of the peculiar behaviour of some of the recently dis- 

 covered radio-active substances, notably radium. 

 About 130 pages are devoted to a description of the 

 various kinds of rays, their origin and physical 

 properties. The part dealing with the electric arc is 

 very complete and clear, and embraces all one could 

 wish to know to ensure an intelligent application of 

 the arc lamp in the treatment of disease. 



Following this is a series of chapters dealing with 

 the action of light on the various forms of life, from 

 the most elementary to the highly complex human 

 subject. In this section the action of light from both 

 natural and artificial sources is treated very thoroughly. 

 It is quite evident that the author has devoted her- 

 self to a large amount of painstaking experiment, the 

 valuable results of which are recorded in the pre- 

 sent volume. According to her, the mercury vapour 

 lamp has not justified the expectations regarding it 

 as a therapeutic agent. 



The second half of the book is taken up with the 



therapeutic applications of the various forms of light. 



This part will be of special interest to medical men, 



especially those who are engaged in this line of work. 



NO. 1838, VOL. 71] 



Sun, arc, and incandescent light baths are treated most 

 fully, together with their use in those diseases in which 

 the author has found them respectively useful. The 

 indications are, in every instance, based on spectro- 

 scopic analysis, and full details of the proper technique 

 are given for every variety of application. Several 

 forms of bath cabinet are described, as well as arc and 

 other lamps for local treatment with concentrated 

 light. 



While the author is rather emphatic on the necessity 

 for employing lamps of large amperage — quantity 

 being as essential as quality — yet she speaks highly 

 of certain small lamps the efficiency of which was 

 such as to necessitate their replacement by lamps of 

 greater power in the light department of the London 

 Hospital. The reason for this praise is seen, later on. 

 to be related to the comparative cost of the lamps — the 

 smaller being sold and maintained at a fraction of the 

 cost of the Finsen, and their efficiency is at least in 

 proportion to this cost. According to the author, the 

 great advantage of a lamp of high amperage, like the 

 Finsen, is that we get not only the short and high 

 frequencies of intense chemical activity, but also the 

 frequencies of long wave-lengths having great ampli- 

 tude and penetrability — a combination which is 

 essential to ensure the best success. In the smaller 

 lamps these long wave-lengths of great amplitude are 

 not present in such abundance because of the lesser 

 amperage and smaller carbons. The results which the 

 author has obtained in many diseases not generally 

 subjected to light treatment will come as a surprise to 

 those who have not kept closely in touch with modern 

 light therapeutics. 



The applications of the various coloured lights, as 

 also those of the invisible spectrum rays, are fully 

 discussed. A short chapter is given to the considera- 

 tion of n-Rays and one to the Alpha, Beta, and 

 Gamma rays of radio-active substances, their physical 

 properties, actions, and therapeutic uses. An in- 

 teresting chapter is that on fluorescence, fluorescent 

 stimulation, and sensitisation of tissues, and the book 

 closes with a chapter on the pernicious effect of sun- 

 light and the pathological effects of electric lighting. 

 The book can be confidently recommended. It will 

 be found of great interest to most students of natural 

 science. Regin,\ld Morton. 



A BOOK ON INK. 

 Inks : their Composition and Manufacture. By 

 C. Ainsworth Mitchell, B.A. (O.xon.), F.I.C., and 

 T. C. Hepworth. Pp. xiv + 251; with 46 illustra- 

 tions, including 4 plates. (London : Chas. Griffin 

 and Co., Ltd., 1904.) Price ys. 6d. net. 

 T ITERA scripta manet; but the permanence of the 

 writing depends upon the quality of the ink. 

 Certain papyri of ancient Egypt, now deposited in the 

 British Museum, contain the earliest ink-written re- 

 cords so far brought to light. A roll dating from 

 2500 B.C. still bears decipherable characters, and frag- 

 ments of papyri have been found by Prof. Flinders 

 Petrie in a tomb to which the date 3500 B.C. is ascribed. 

 If the origin of the use of ink is 'ost in antiquity, at 



