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tococcus earlier described as Leuconostoc mesenteroides. However, ten 

 years ago my collaborator Perquin found that this so-called 'dextran'- 

 formation could also be caused by a quite different rod-shaped bacte- 

 rium which, remarkably enough, had been described in 1897 by 

 Marshall Ward as one of the components of the 'ginger-beer plant'. 

 The same has lately been found in England by Scarr. 



Another interesting observation was recently made by Verhoeven 

 who found that the nitrite sometimes present in molasses and which 

 may give rise to serious complications if the molasses are to be applied 

 in the fermentation industry, owes its origin to nitrate-reducing bacte- 

 ria accumulating in the crude juice almost immediately after it leaves 

 the diffusion battery. 



It is generally known that troublesome deviations from the normal 

 course of manufacture, owing to an invasion by microbes, are not at 

 all restricted to the food industries. It has been realized for some time 

 that several organic raw materials which on the whole are unsuitable 

 as human or animal food are readily accepted as such by special types 

 of micro-organisms. This may lead to various undesirable industrial 

 implications ; I need only cite the mildewing of cotton fabrics as an 

 example. The important work performed in the Shirley Institute has 

 made it possible to devise effective counter-measures. In the mildew- 

 ing of fabrics and related materials, the microbial nature of the trouble 

 has been evident almost from the beginning. This cannot be said of 

 slime formation in paper mills which may seriously interfere with 

 production, and which in the past has often led to expensive interrup- 

 tions in the process, caused by the need for cleaning. Since in later 

 years it was shown that bacteria are nearly always responsible for the 

 slime production, this trouble has almost completely been overcome 

 by adding biocides like pentachlorophenol or organic mercury com- 

 pounds to the pulp mass. 



We all know, too, that an organic construction material like wood 

 is, under certain conditions, liable to disastrous attacks by special rep- 

 resentatives of the microbe world, the more or less ubiquitous wood- 

 destroying fungi. The response of mankind has been a wood preserva- 

 tion industry which in later years has owed much to the extensive re- 

 search work done in various laboratories, amongst which the Forest 

 Products Research Laboratory at Princes Risborough holds first place. 



It therefore seems justified to conclude that all industrial leaders 



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