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the vessel in which the anatomical preparations were pre- 

 served. His authority was Dr. De Morgan, of the Middlesex 

 Hospital, who stated to him a few days since that he had 

 succeeded by that means in preserving classes of animals 

 which all other means had failed in preserving, namely, 

 Molluscae, Zoophytes, and Acalephse. 



Dr. Calvert also read a Paper " On the Employment of 

 Galvanized Iron for Armour-plated Ships." 



The Author stated that no doubt many gentlemen present 

 were acquainted with the fact that he had been for some 

 time past engaged in ascertaining the chemical composition 

 of various woods employed and susceptible of being employed 

 in the navy. On a recent visit to one of the dockyards he 

 found that while the armour-plates were fixed against a layer 

 of teak, the ribs of the ship were of oak, and that the iron 

 bolts which were to fasten the plates were to pass through 

 the oak ribs. It occurred to him that the inconvenience 

 which would probably result from the action of the oak upon 

 the iron might be obviatfed by substituting galvanized iron 

 bolts for those now in use, and he therefore instituted a series 

 of experiments, the results of which he had great pleasure in 

 laying before the meeting. 



The first series of experiments consisted in having driven 

 through large pieces of oak, bolts and screws of iron and 

 galvanized iron prepared by his friends, Messrs. Richard John- 

 son and Brother, of Dale-street, Manchester, which were then 

 immersed in soft and sea water for the last three months. The 

 results clearly showed, first, that the friction did not remove 

 the zinc from the galvanized iron ; secondly, that the oak and 

 galvanized bolts were unchanged ; whilst in the case of the 

 iron bolts, they were much rusted, and the pieces of oak had 

 become quite black by the formation of tannate and gallate 

 of peroxide of iron. During the experiments the waters were 

 changed every week, and those containing the galvanized iron 



