Jan. 13, 18S8.] 



SCIENTIFIC NE\VS. 



41 



Chemistry and Heat— Laws and Definitions. By R. G. 

 Durrant, M.A., F.C.S., Assistant Master at Marl- 

 borough College. London : Rivingtons, 1887. 



This little book of ninety-nine pages contains the es- 

 sence of many big volumes. It is, in fact, the sort of 

 condensation which a clever and very industrious student 

 aims at making for himself while going through his 

 course of reading — aims at, we say, but rarely reaches. 



Laws and definitions are given with accuracy and 

 clearness, and good examples are added throughout. 

 The beginner will find it useful as an adjunct to his 

 fuller work, and the advanced student may, with its aid, 

 quickly refresh his memory and re-arrange his facts. 

 For examination purposes it will be particularly 

 valuable. 



The printing and the general get-up are neat and 

 attractive. We have found only one mis-print — on page 

 seventy, NjO being given as N.O — and usually mis- 

 prints in books on chemistry are numerous. 



The Stevens Indicator. Vol. iv., No. 4. 



This journal is the organ of the School of Mechanical 

 Engineering connected with the Stevens Institute of 

 Technology. Perhaps the most noteworthy matter the 

 present number contains is to be found in the addresses 

 delivered to the graduates. Said one of the speakers : 

 " You are to be spared this evening any direct reference 

 to the ' conceit of learning,' but you are asked and ad- 

 vised to bear with the conceit of ignorance. . . . The 

 most disagreeable man about the establishment who 

 perhaps goes out of his way to insult you may be one 

 who can be of greatest use to you." 



Afterwards follows advice on dealing with strikes, 

 " walking delegates," etc., from which it may be gathered 

 that these nuisances are not less rampant in the United 

 States than in Europe. 



A paper on Inter-collegiate boat-racing contains a 

 curious calculation. It is shown that each rower performs 

 work each minute equivalent to the work of seven strong 

 labourers, and at the rate of very nearly one-third of a 

 theoretical horse-power each minute during the race. 



T/ie Photographer's Indispensable Handbook. Compiled 

 by Walter D. Walford, edited by Henry Sturmey. 

 London : Iliffe and Sons. 

 This is a complete cyclopedia on the subject of photo- 

 graphic apparatus, materials, and processes. It is a com- 

 pilation from the catalogues of various firms, and is pro- 

 fusely illustrated. One of the best sections of the book 

 is that on formulae and instructions. A few words on 

 the selection and testing oi lenses would have been 

 acceptable, as if the lens be bad it is impossible to do good 

 work. On the whole we can, however, strongly recom- 

 mend this work to the attention of all those interested 

 in photography, as it plainly brings before the reader the 

 merits and demerits of the various forms of photographic 

 apparatus and appliances. 



Journal of the Scottish Meteorological Society. Series 3 ; 

 Vol. IV., for 1886. 

 Perhaps the most interesting paper in this yearly 

 volume is that comprising the results of the biological 

 work of the Scottish Marine Station. Some years ago 

 this establishment might have been more conveniently 

 called an "aquarium," but now that term has been 

 usurped by places of amusement, we are obliged to give 

 the genuine aquarium a different name. The work done 



has been good. The first portion consisted in deter- 

 mining the local faunas of the Friths of Forth and Clyde. 

 The decapod and schizopod crustaceans have next been 

 reviewed. From a practical point of view the most 

 important study has been the reproduction and develop- 

 ment of the borer, or hag-fish {Myxine glutinosa), one of 

 the deadliest enemies of our food-fishes. A thorough 

 knowledge of this pest is needed, that we may attack it 

 with advantage. Researches on the spawning of her- 

 rings and the spatting of oysters have been carried on at- 

 May Island and at Granton. Two important memoirs 

 have been drawn up by students working at Granton. 

 One of these treats on the " Physiology of the Nervous. 

 System in the Lobster," and the other deals with the 

 phosphorescence of Nycphanes Norwegica. 



THE EFFECT OF LIGHT ON PLANTS. 



THE herbalists of old, after the experience of a life in 

 collecting plants for their medicinal preparations, 

 observed the peculiarities of these plants at different 

 times of the day and night, and even under different 

 phases of the moon. This was long looked upon as a 

 superstitious craze — a remnant of alchemy and magic. 

 The rules of these, herbalists, however, deduced centuries 

 ago after careful observation, are now being explained. 

 Long were they laughed at as mere delusions, but Sachs, 

 the highest authority on the physiology of plants, has 

 demonstrated their truth. His observations show that 

 the amount of starch present in the leaf of any given 

 plant varies considerably under different circumstances. 

 When the sun shines brightly and directly upon the 

 plant, without much wind, starch is formed very rapidly. 

 During the night, again, this starch generally disappears. 

 Accordingly, leaves collected at sunset are full of starch, 

 whereas the leaves of the same plant gathered at day- 

 break are quite destitute of it. Sachs has given us the 

 best means of detecting the existence of starch in leaves. 

 The leaf to be examined is first plunged into boiling 

 water for about ten minutes, then taken out and digested 

 in alcohol for about the same time. The whole of the 

 colouring matter is thus extracted, and the leaf is left 

 quite white. If the leaf be now placed in an alcoholic 

 solution of iodine, the existence of starch can be instantly 

 detected. If much starch be present, the leaf turns 

 blue-black ; if the quantity of starch be but small, it 

 becomes only brown ; if there is no starch, no change 

 occurs. The veins of the leaf form a pale network on 

 a dark ground, rendering it a very beautiful object. 

 Sachs has not yet succeeded in preserving one of these 

 specimens of venation beyond a few hours. The varia- 

 tions in the amount of starch in the leaves of plants at 

 different periods of the day and night arrest the ob- 

 server's attention, for they render it possible that the 

 amount of some of the poisonous alkaloids formed by 

 the decomposition of albuminous substances may vary in 

 a similar way. This is quite a new study. The in- 

 fluence of light on plants may yet prove of great prac- 

 tical importance in medical art. 



A Large Meteorite.— On August 13th last there fell 

 at Taborg, in Russia, a meteorite of which the larger 

 fragment weighed upwards of 250 lbs. It is strongly 

 magnetic, and contains abundance of native iron. 



