BACTERIZED PEAT 87 



change can be effected even more quickly than with 

 bacteria by treating the raw peat with alkalies, but 

 so far it had not occurred to anyone that peat could 

 be valuable as a manure, except when it had been 

 well rotted by natural means. Farmers and horti- 

 culturists would have probably long rested content 

 with buying the peat used in stables as bedding, and 

 storing it up to rot into good condition, though, as 

 has been done in practice, they could have hastened 

 the process by mixing it with lime. 



The aim of those working at the problem, how- 

 ever, was not to discover a fertilizer, but to find a 

 medium in which the bacteria connected with the 

 fixation of nitrogen could be cultivated and put on 

 the land. In the peat treated with aerobic bacteria 

 they found such a medium, which was far superior 

 to anything they had hoped for. When once the peat 

 has been treated with these bacteria, from between 

 20 to 25 per cent, of it is available as soluble plant 

 food. To effect the change all that is necessary is 

 then to keep the peat moistened at a temperature of 

 26 C. (79 F.) for about a week. Steam can then 

 be forced through the mass for as long as is desirable 

 to insure that all organisms, bacterial or other, have 

 been destroyed, and the result is a sterile medium, 

 neutral or slightly alkaline, and suitable for the 

 cultivation either of plants or of bacteria. 



Once a suitable medium had been found for the 

 growth of Nitrogen-fixing organisms, the question to 

 be settled was what bacteria could best be utilized 

 for the purpose in view. As has been seen in earlier 

 chapters, if the best obtainable results were to be 



