132 Commercial Gardening 



be managed by a boy, but it is necessary to make sure from time to time 

 that there is no interference with the proper discharge of the electricity 

 due to leakage down damp poles or to defective insulators. An installation 

 of the simplest type, for experimenting on from 5 to 10 ac., a dynamo 

 being available, would probably cost about 100. In the same conditions 

 an installation for 60 ac. might cost about 225. A complete outfit 

 for 30 ac., including engine, dynamo, and shed, would involve an ex- 

 penditure of something like 300, but an installation for twice the area 

 would not cost more than another 100. There is a probability of the 

 expense being decreased in the future." It is claimed for this electrical 

 process that there is an increased yield accompanied by accelerated pro- 

 duction, and the plants (Lettuces have been chiefly experimented on) are 

 of a deeper green. 



It is always wise to pay attention to experiments, even when carried 

 out by those who have had little or no training in horticultural prac- 

 tice, but we have no hesitation at present in saying that 6 or 8 

 per year spent on trenching an acre of ground 2 ft. to 3 ft. deep would 

 yield larger supplies of nitrates and crops immensely superior to anything 

 that can be achieved by " electrical " culture. [j. w.] 



13. SOIL ANALYSIS 



All growers, whether amateur or professional, are aware of the difficulty 

 of estimating just what form of plant food is deficient, and usually it is 

 only by more or less costly experiments that some basis can be obtained. 

 Of course many men simply depend on certain quantities, adding such to 

 the soil whether the plants require it or not, until soil sickness occurs, and, 

 in consequence, many pests and plant diseases. 



To obviate the above disadvantage, and to obtain a useful knowledge 

 of the composition of the soil, analysis, both chemical and physical, is 

 resorted to, and it is proposed to deal with this in as simple a way as 

 possible. It must of course be thoroughly understood from the beginning 

 that to arrive at an accurate analysis requires much expensive apparatus 

 as well as a long course of practice and study, but enough information 

 will be given to enable the studious grower to obtain many useful data, 

 to save him from wasting his time over unnecessary experiments, and 

 also to open a new field for research and profit. 



In the older methods of analysis the soil after preparation was digested 

 by strong acids, hydrochloric being the chief. This extracted all the food 

 that might or might not be available at some future period, but gave no 

 idea of what was immediately available for the plant's use. In conse- 

 quence of this the results were so misleading that soil analysis was spoken 

 of with scorn. Often enough one ingredient was said with truth to be 

 in large quantity, but the growing crop would show symptoms of starv- 

 ing for want of that very constituent. As an instance, clays and clay 



