( nao ) 



with which an exsiccator is filled and into which the plates are 

 in trod need. 



Bj streaiving a yonng tilm from a liqnid cnltnre on tlie said solid 

 medium already on the second day nearly pure slightly turbid 

 colonies are obtained, quite distinguishable by their size and their 

 slimy and lightly pink-coloured appearance. Such a colony, when 

 early inoculated into the above apparatus forms, after some days, 

 another bacterial film. 



The methan, being in all the experiments the only source of carbon, 

 necessarily at the same time must serve as food and as source of 

 energy. 



The quantity of carbonic acid in the culture flask indicates 

 the amount of methan which has served as source of energy. 

 The quantity of methan used for the formation of the bacterial 

 bodies may be measured by subtracting the quantity of produced 

 carbonic acid, expressed in cc, from the volume of disappeared methan. 



So for example it was found that in an experiment in which were 

 added successively 225 cc. CH' and 320.7 cc. O' to 102 cc. ot 

 liquid, the flasks contained after a fortnight 



78 cc. CO"' 



no CH^ 



172 cc. 0'. 



In the culture liquid 21 cc. of carbonic acid were solved, so that 

 126 cc. of methan had been assimilated for building np the bacterial 

 bodies, and 78 -[- 21 cc. CH' for the respiration, 148.7 cc. of oxygen 

 being assimilated. 



Another experiment gave the following result. 

 Successively added 200 cc. CH^ 

 and"^ 331cc. 0\ 



to J 08.5 cc. liquid. 



After two weeks the gas contained 



72.8 cc. CO 

 39 cc. CH^ 

 138 cc. 0^ 

 In the culture liquid 18 cc. of carbonic acid WT.re solved. Hence, 

 73.2 cc. CH' had been assimilated for the formation of the bacterial 

 bodies, whilst 90.8 cc. CH' were converted into CO'. 



Some oxidation experiments were performed with permanganate 

 and sulphuric acid, in order to prove that a large quantity of organic 

 material had accumulated. Thus, 100 cc. of the culture liquid, 

 described in the first experiment, consumed: . 



