146 CASEIN. 



several sheets of the prepared paper, or of such paper and 

 linen, can be fastened together to make a more or less thick 

 and dense material. Finished cardboard goods, boxes, etc., 

 can also be covered in this way with such moth paper. It 

 is also advantageous to fasten cotton wool on to paper oi- 

 lmen by means of the formalin-casein adhesive or by sewing, 

 and then impregnate the wadding with formaldehyde. 



If, on the other hand, greater importance is attached to 

 the waterproof character of the preparation, this result may 

 be attained in various ways, for instance, by steeping the 

 paper with a solution of paraffin in benzol, a solution of 

 shellac and borax, alcoholic solutions of resin, or by coating 

 with viscose (cellulose tetracetate), either in conjunction 

 with dissolved casein or after treatment with the latter. 

 Fine fabrics may be waterproofed by the same means or 

 with the conjunction of alumina, aluminium mordants, am- 

 moniacal copper oxide, oil, etc. ; in any case, however, a 

 copious amount of formaldehyde must be used. If the effect 

 be found to have weakened by lapse of time, it can be 

 renewed by the application of formalin (40 per cent, for- 

 maldehyde). 



Materials rendered in this manner proof against germs, 

 water and insects, are manifestly applicable to a large num- 

 ber of purposes. Among these may be mentioned the storing 

 and conveyance of foodstuffs, especially in humid climates ; 

 also as wrappers for anatomical and zoological preparations, 

 corpses and other objects liable to decomposition. Further- 

 more, they may replace the more expensive oiled linen wher- 

 ever a light, but resistant, waterproof and cheaf wrappering 

 is needed. Special attention is called to the manufacture of 

 impregnated paper bags, which would meet with a ready 

 sale for storing clothes ; also portfolios for documents and 

 antiquities, such as lace, in museums and collections. 



