ON THE PROGRESS OF SCIENCE. 21 



edges, being gummed in the operation, exactly meet ; when they are 

 pressed firmly together, and the now perfected cot dropped through the 

 machine and another length drawn in, to undergo the same process. 



That ingenious contrivance, the sewing machine, appears to be coming 

 into universal use. Since the first invention, the machine has been greatly 

 perfected and simplified, and has, we believe, nearly attained its greatest 

 excellence, in a recent invention not yet made public. 



The newly invented life-boat, to which the prize given by the Duke of 

 Northumberland, Eng., was awarded last season, has unfortunately proved 

 a failure. This boat, it will be remembered, was selected from a competing 

 number of two hundred and eighty, which were urged on the Committee 

 through plan or model. 



Calvert, of Manchester, Eng., has recently introduced a valuable im- 

 provement in the process of smelting iron, by previously removing the sul- 

 'phurous vapor from coal and coke. The results have been most satisfac- 

 tory, the strength of the iron produced by this process being about 40 per 

 cent, greater than that made in the ordinary way. 



The subject of the artificial production of fish, started in France a few 

 years since by MM. Sehin and Remy, has been taken up in England during 

 the past year with great success. A little work, containing full instructions 

 for multiplying fish of nearly every description to an almost incalculable 

 extent, has recently passed through several editions in London. 



The curious and useful applications which are now so frequently made of 

 the improvements in photography, are strikingly illustrated by the follow- 

 ing notice made to the French Academy by M. Milne-Edwards of an un- 

 published book of MM. Rousseau and Deveria : Photographic Zoologique. 

 This wonderful book does not introduce any new processes of photography, 

 but presents an extremely important application of the art of photography 

 to zoology. The plates which compose this work present as yet only in- 

 complete essays, which, however, partly realize the advantages hoped from 

 the application of this new arc to zoological studies. M. Milne-Edwards 

 remarked that the zoologist has often occasion to represent a multitude of 

 details which escape the naked eye, and yet which it is necessary he should 

 show. To show them the draughtsman is obliged to magnify them, as if 

 they were seen through a magnifying glass, and the objects thus repre- 

 sented rarely have their natural aspect ; consequently, the zoologist 

 always takes care to use two sorts of images ; figures d' 'ensemble, not mag- 

 nified, and figures of certain characteristic parts, more or less magnified. 

 In the plates presented to the Academy by M.M. Rousseau and Deveria, 

 such as those representing the Euryale, the Agaricie, &c., the details of 

 structure can be perceived by the naked eye no more than in nature ; but 

 if the observer uses a magnifying glass, they appear to the observer's eye 



