SUNDRY APPLICATIONS OF CASEIN. 149 



gelatine have been proposed in place of glass, celluloid alone 

 has been able to hold its own for this purpose. Neverthe- 

 less, this substance also has its defects, being in the first 

 place highly inflammable, subject to electrical discharges 

 which spoil the photographic image, liable to curl in the 

 various baths, and, finally, very dear in comparison with 

 glass plates. 



The use of casein for the purpose in question appears to 

 have solved the difficulty of finding a material that is free 

 from the above-mentioned inconveniences. 



WOOD- CEMENT ROOFING PULP. 



This new roofing pulp has the advantage over tarred 

 pulp in being fire- as well as water-proof, and of not softening 

 with heat. It is made of cellulose pulp board, painted over 

 with the following composition : 



Slaked lime 100 parts. 



Casein and sodium bicarbonate . . 10 



the latter being dissolved in water, stirred up to a pap with 

 the lime, and gradually thinned down to the consistency of 

 syrup. Four applications are generally sufficient to produce 

 a coating of the requisite thickness. 



The sheets may also be dipped in the composition, the 

 latter being correspondingly thinned down for this purpose. 

 The waterproof character is increased, and a fine gloss im- 

 parted, by topping the finished article with a coating of 

 shellac and borax solution. 



CASK GLAZE OF CASEIN AND FORMALDEHYDE. 



The wooden casks used for the transport and storage of 

 wine, beer, etc., are liable to become infested with mould 

 fungi and other bacteria when lying empty, and must there- 

 fore be carefully cleansed, before use again, with boiling 

 water and some disinfectant, such as lime, etc., and then 

 dried. Even then, no security exists against the contamina- 



