540 REPORT OF COMMISSIONER OF FISH AND FISHERIES. [8] 
commence till the beginning of October, it will be an easy matter in small 
ponds, especially if one takes care to get a number of extra oxen‘ for 
this extra work, to beemployed, of course, only temporarily for this specific 
purpose. It will be found most profitable to employ for this work oxen 
which, being well fed during the season of labor, may often be sold with 
advantage, after the work is done, to butchers for fattening. The cap- 
ital invested will thus be profitably reduced. 
Possibly it would be found advantageous to use a steam-plow in very 
large ponds, but this will of course depend on the locality, the means 
at the farmer’s disposal, &e. 
Under all circumstances it is not only a short-sighted policy, but 
actually an injury to the national wealth, if any farmer, who has the 
means, does not drain at least those of his ponds where this can be done 
easily, and periodically devote them to agricultural purposes, thus de- 
riving the greatest possible benefit from every part of his property.. 
There are many farmers who are unfortunately compelled to obtain their 
manure from abroad, partly on account of insufficient harvests from 
poor fields, partly because industrial enterprises necessitate a greater 
production. Many farmers who possess arable ponds, unfortunately 
have recourse to the comparatively easy system of buying artificial con- 
centrated fertilizers, before they have made careful and repeated exper- 
iments, to determine whether these fertilizers will suit their peculiar 
soil, and the consequence is that they soon become convinced by bitter 
experience of the mistakes they have made, which, moreover, in most 
cases has proved a considerable expense. 
In my opinion it would be far more practical, and, at least as long 
as agricultural chemistry, owing to the great and general ignorance of 
the nature of soils is not able to give absolutely reliable advice as to 
the application of fertilizers, much more rational, to make use of those 
advantages furnished by every locality, 7. e., to use that fertilizer which, 
so to speak, has grown on the same soil (the mud of ponds is nothing 
but a portion of the soil), and will, therefore, be particularly suitable, 
can easily be assimilated, and with very little trouble can be transferred 
from the ponds to the neighboring fields. No harm will be done, even 
if in some cases this fertilizer is mixed with other substances not hav- 
ing such strong fertilizing qualities. In using mud from the ponds as 
manure, the plants growing on fields, whose soil has thus been improved 
will of course draw from the ground only those substances needed for 
their growth. In this manner a circulation, on a small scale, of the most 
valuable mineral substances serving as food for plants, is inaugurated, 
atmospheric influences uniting with these during the growth of the 
plant ; whilst the mineral substances above referred to, during this pro- 
cess, again return to the inexhaustible source whence they came, of 
course excepting that small portion which was taken away in the fish, 
or which, during the flooding of the upper portions of the pond, does not 
return to it. 
