January 19, 192; 



NATURE 



71 



Reiter," and — curious association — two short 

 notices relating- to the Emperor William I. These 

 deal with the Frankfort Congress of 1863, and 

 with episodes in 1870 at Ems, and at Sedan. The 

 notes of the conversation with the French Ambas- 

 sador Benedetti at the former place (July 13 and 

 15, 1870), and with Napoleon III. at the latter 

 place (September 2, 1870), are of historical 

 interest, and are among the few papers of per- 

 manent value contained in the book. 



The price of the brochure, which is issued in 

 paper covers, is stated to be 100 marks, which, 

 considering the present value of German currency, 

 is not excessive, however significant of Germany's 

 financial straits. The book is admirably printed 

 on excellent paper, and is suitably illustrated. It 

 does credit, in fact, to the eminent firm by which 

 it is published. The war and its consequences 

 have evidently had no detrimental effect on the 

 typographical excellence of book production in 

 Germany. 



Fish Preservation. 



Fisheries — England and Wales. Ministry of 

 Agriculture and Fisheries. Fishery Investiga- 

 tions : Series i. Freshwater Fisheries and Mis- 

 cellaneous. Vol. 2, No. I, The Methods of 

 Fish Canning in England. Pp. 25. (London : 

 H.M. Stationery Office, 192 1.) 25. 6d. net. 



THE development of methods of preserving 

 fish was a matter of national importance 

 during the war, and the present account is 

 founded on investigations started in that period. 

 The fish used for canning are mostly surface- 

 feeding and living fish, such as sprats (or 

 bristling), sardines (or pilchards), tunny and 

 bonito, herring and mackerel, the only other fish 

 of any importance being the salmon caught in 

 America on its migration to fresh water for breed- 

 ing. Of British fish there is a great excess of 

 herring in the normal fisheries, and, given suitable 

 fishing gear, large quantities of sprats can also 

 be obtained on all coasts. Mackerel are at times 

 abundant, but there is little certainty of heavy 

 catches year by year,; pilchards are local to Corn- 

 wall, and the immature forms (sardines), so ex- 

 tensively tinned in France, Spain, and Portugal, 

 are not caught in quantity. There was one 

 British sprat cannery before the war, but herrings 

 were put up at the great herring ports in oil or 

 with tomato, the product being in some cases 

 excellent. Excess sprats were generally used for 

 manure, while herrings were salt-pickled and 

 barrelled for export, the price being two or three 

 NO. 2725, VOL. 109] 



for a penny. The latter is an " unspeakable " pro- 

 duct, which has never found favour in this 

 country, and fresh methods of preservation are 

 urgently requisite for the utilisation of herrings 

 as a cheap form of food. The markets, too, of 

 Central and East Europe, which took most of this 

 product, are disorganised, and it is doubtful 

 whether they can ever be recreated, as there 

 would seem to be a real improvement in Continen- 

 tal taste, brought about by the temporarily 

 improved food conditions of the war. 



TTie success of different kinds of fish as canned 

 products depends largely on the fat which lies 

 under the skin and between the muscles. Salmon 

 is canned or frozen in air (dry frozen) on the 

 Pacific coast almost immediately when caught, 

 certainly before rigor mortis has set in ; the same 

 is, to some degree, true also of the Norwegian 

 sprats (bristling), of which there are about eighty 

 factories in operation. The difficulty in Great 

 Britain is that no port has a herring or sprat 

 season extending through more than three or four 

 months, and a factory with modern appliances and 

 trained packers cannot be run profitably for such 

 a short season. The fish required at other times 

 must be brought in by rail, and this doubles the 

 cost, while the actual fish has passed through its 

 rigor and is deteriorating. It would seem neces- 

 sary to get the fish as fresh as possible and to 

 discover some method of preservation in bulk for 

 subsequent packing, the process being one which 

 would in no wise alter its composition or flavour. 



Experiments with brine freezing and subsequent 

 cold storage are described, but difliculty was ex- 

 perienced in the caking of sprats into masses and 

 the salting, due both to the small size of the fish 

 and to an excessive cold-store temperature " just 

 under 30° F." Both these difficulties might per- 

 haps be got rid of, but the total cost of the actual 

 freezing, storage, transport, etc., would probably 

 average 3d. per lb., which only a first-rate product 

 could bear. Unfortunately, British sprats, as at 

 present caught, are shown to be by no means such 

 a product, being indeed much inferior to the Nor- 

 wegian. According to the tables, they varied in 

 fat from 5 to 23 per cent., protein being 15 to 

 20 per cent., ash about 15 per cent., the rest 

 being water, which, with fat, roughly forms 

 80 5 per cent. The problem is to catch sprats of 

 the right composition for pickling. The English 

 fish is winter and spring caught, while the Nor- 

 wegian fishery is in summer and autumn. The 

 reproductive cycle has doubtless something to do 

 with the quality, but little is as yet known of the 

 life-history of the English fish. The difference 

 lies probably, not in the fat contents, but in other 



