Jan. 6, 1881] 



NA TURE 



215 



" 1 2. C. toll. The subject of a very extensive fishery 

 on the coast of Sumatra for the sake of its roes, which are 

 salted and exported to China, the dried fish themselves 

 being sent into the interior of the island. The fish is 

 called ' Trubu ' by the Malays, is about eighteen inches 

 long, and it is said that between fourteen and fifteen 

 millions are caught annually. 



"13. C. scoinbrina. The 'oil sardine' of the eastern 

 coast of the Indian Peninsula." ' 



These quotations will show the value and importance 

 as well as the interest of the systematic and descriptive 

 part of this volume, not a page of which is without some 



\.\, Vv 



Toxoles facttlator. 



lines of most instructive reading, in many cases sufficiently 

 so as to tempt one to turn " Ichthyologist " on the spot- 

 We strongly recommend the reader to turn at once to the 

 pages on the Salmonidffi. This portion too is illustrated 

 with many excellent figures, two of which, through the 

 courtesy of the publishers, we are permitted to reproduce 

 — the first is of a fish belonging to the genus Toxotes. 

 Two species of this genus are known from the East Indies, 

 one of which (7". Jnculd/or) is the more common, and it 

 ranges to the north coast of Australia. It has received 

 its name from its habit of squirting a drop of water at an 

 insect which it perceives close to the surface in order to 



Skull of Plagycdus/erox. 



make it fall into it. The Malays, who call it " Ikan 

 sumpit," keep it in a bowl in order to witness this singular 

 habit, which it continues even in captivity. 



The second woodcut represents the bones of the head 

 of one of the lirgest and most formidable of the deep-sea 

 fishes. Of the genus Plagyodus but one species is known 

 (Z'. fcrox). It has been found off Madeira and in the sea 

 off Tasmania. Other species have been noticed from 

 Cuba and from the North Pacific, but it is doubtful if 

 they differ specifically from P.ferox. The fish grows to a 



ulse and references to works on the Herring. 



length of six feet, and from the stomach of one specimen 

 have been taken several eight-armed cuttle-fish, Crustacea, 

 Ascidians, a young brama, twelve young boar fishes, a 

 horse-mackerel, and one young of its own species. The 

 stomach is coeeal, the commencement of the intestine has 

 extremely thick walls, its inner surface being cellular, like 

 the lung of a reptile, it has no pyloric appendage. All the 

 bones are extremely thin, light, and flexible, containing very 

 little earthy matter. Very singular is the development of 

 a system of abdominal ribs symmetrically arranged on 

 both sides and extending the whole length of the abdomen. 

 Perfect specimens are rarely obtained on account of the 

 want of coherence of the muscular and osseous parts, 

 caused by the diminution of pressure when the fish 

 reaches the surface of the water. The exact depth at 

 ^\\\c\\ Plagyodus ferox lives is not known; probably it 

 never rises above a depth of 300 fathoms ; but woe betide 

 any rash intruder that dares to descend into the realms 

 of its abyss. 



The volume closes with some directions for collect- 

 ing and preserving fishes — when practicable fishes when 

 dead should be set to swim in spirit. But we must not 

 quote any more, so leave the curious reader to find out 

 the details of how, having caught his fish, he can cook it 

 so as to make it of value for some national museuin. 



SULPHURIC ACID AND ALKALI 

 A Thi-oretkal and Practical Treatise on the Manufacture 

 of Sulphuric Acid and Alkali, with the Collateral 

 Branches. By George Lunge, Ph.D., F.R.S.E., Pro- 

 fessor of Technical Chemistry at the Federal Poly- 

 technic School, Zurich (formerly manager of the Tyne 

 Alkali Works, South Shiel s). Vol. III. (J. Van Voorst, 

 1880.) 

 '"I'^HE publication of the third and concluding volume 

 -L of Prof. Lunge's excellent work follows wonderfully 

 soon on that of the first and second. This volume, which 

 fully equals the other two in accuracy of description and 

 clearness of style, is devoted to the subsidiary processes 

 lying alongside of the main channel of Leblanc's great 

 discovery. We first find a chapter on the ammoniacal 

 soda process now rising, through Solvay's exertions, into 

 well-merited and formidable competition with its older 

 rival. The ash made by this theoretically beautifully 

 simple and practically most original process is very pure, 

 containing from 98 to 99 per cent, of Na.jCOo, and free of 

 course from the impurities common to Leblanc's ash of 

 caustic soda and sulphide of sodium. 



But this Solvay's ash is less dense than that made by 

 the old pl.in, and both German and English manufac- 

 turers are now making a Leblanc ash of 98 per cent, free 

 from sulphur and of a dense quality. The struggle, says 

 Lunge, is not now one of purity, but merely of price, and 

 so far Leblanc soda is holding its own. Here however 

 the beneficial action of competition is seen : if Messrs. 

 Brunner, i\Iond, and Co., of Northwich and Sandbach, 

 were not turning out from 35 to 40 tons of Solvay ash 

 per diem, I cannot help thinking that the Leblanc soda- 

 makers might have felt inclined to rest content with their 

 previous performances. There is of course no chance of 

 this new process turning out the old-fashioned plan until 

 the chlorine of the common salt can by this new method 



