BACTERIA. 87 



and bacteria, the disease will develop in a varying degree, 

 according to the proportion of bacteria. If, however, these are 

 only added after the completion of the primary fermentation, 

 the disease will not appear at all. The greater the proportion 

 of nitrogenous matter in the liquid, the sooner it will become 

 viscous ; even liquids which do not contain sugar can be made 

 ropy by these species ; when the nutritive liquid contains much 

 sugar, the fungus develops very feebly, and in pure sugar 

 solutions the phenomenon does not make its appearance 

 at all. 



VANDAM found in English beers an aerobian Bacillus 

 viscosus, which occurs as small rods, single or united in 

 chains consisting of two, three, or more links ; in the centre 

 of these rods spores are formed. This bacillus develops best 

 at about 30 C., and produces a slimy mass in brewers' wort, 

 which under the microscope proves to consist of zooglcea forma- 

 tion. After the lapse of some time the liquid has the consistency 

 of albumen. No gas is evolved, but the liquid acquires a peculiar 

 odour. On meat-juice gelatine mixed with sugar and on 

 wort gelatine the growth develops freely. The viscosity of 

 the liquid does not seem to depend on the quantity of nitro- 

 genous matter present. This species is incapable of producing 

 disease in beer unless it is thriving well and is introduced in 

 large quantities into the wort before or during pitching. Like 

 the forms discovered by VAN LAER, this species ferments milk- 

 sugar ; and, according to VANDAM, it is easy to detect it in 

 yeast, even in traces, simply by introducing a sample of the 

 latter into nutritive liquid containing milk-sugar, a growth of 

 this species soon making its appearance in the upper part 

 of the liquid. 



. BROWN and MORRIS mention a Coccus form which also 

 seems to produce ropiness in English beers. This species 

 occurs as diplococcus and in tetrads, and gives yellow wax-like 

 colonies on meat-broth gelatine. The disease made its 

 appearance in the beer after a lapse of six to eight weeks; 

 but it was not usually possible to produce it by inoculation 

 with pure cultures of the species in sterile beer. Close to 

 the fermentation room there was a pork-butcher's premises, 

 in which putrefying matter had accumulated ; after this had 



