166 QUEENSLAND AGRICULTURAL JOURNAL. [1 Mar., 1899. 
spread over the country, and are active agents in destroying the fertility of 
other lands. The experiment farm then comes to the rescue. It shows 
the farmer how he can overcome the difficulties which beset him. It points out 
what is wanting in his soil, it shows him how to improve it in the most economical 
manner, and thus is the direct agent in retaining the tillers of the soil on their 
old lands, and enabling them to add to the wealth of the country without 
going beyond their own district, whilst the new lands are left available for new- 
comers. In this way the experiment farms more than repay the cost of their 
maintenance. 
Professor Paul Wagner, Ph.D., Director of the Government Agricultural 
Research Station, at Darmstadt, Germany, one of the greatest authorities on 
manurial experiments, lays down certain rules for carrying out experiments in 
this direction which are simple and clear, and restrict the experiments within 
reasonable and practical limits, which enable them to be undertaken by any 
practical, intelligent farmer. 
Given that a certain portion of a farm has become unproductive, or was 
originally of such a nature as to be considered comparatively valueless for the 
production of payable crops, the question naturally arises, ‘ Can the produc- 
tiveness of any given area of land be increased by the application of manures 
of commerce?” By ‘manures of commerce” is meant, not farmyard manure, 
but what are known as artificial fertilisers—the principal of which are 
phosphate, nitrates, and potash. 
How is the question to be answered ? Professor Wagner says, ‘‘ Make a 
simple experiment.”’ Take two small plots of the land in question. Leave one of 
them without manure, and dress the other with some artificial manure containing 
nitrogen, phosphoric acid, and potash. Any difference in the yield obtained 
from these plots furnishes at once an answer to the question set. And, further, 
supposing an improvement in quantity or quality, or in both, to have resulted 
from the manuring, then, by comparing the cost of the manuring with the 
marketable value of the produce, an insight is obtained into the extent of the 
profit that might result by the adoption of the manure thus investigated. 
Here are some examples of experiments made with the object of ascertain- 
ing the value of the fertilisers :— 
1. A field of barley yielded per acre :— 
Straw. Grain. 
Tons cwt. qr. Ib. 
Manured so 2 iss BY OR Tr 3,044 lb., or 563 bushels of 54 1b. 
Unmanured ... 1 1 8 8 aE 1,999 lb., or 37 bushels of 54 Ib. 
Increase ... 14 0 18 ay 1,045 lb., or 19% bushels of 54 1b. 
2. A field of oats yielded per acre :— 
Straw. Grain. 
Tons ecwt. qr. Ib. 
Manured ... 2 1 1 10 ... 2,676 1b., or 744 bushels of 36 Ib. 
Unmanured ... 1 10 1 2 ... 1,472 1b., or 41. bushels of 36 Ib. 
Increase ... iil @ & on 1,204 1b., or 33% bushels of 36 1b. 
3. Another field of oats yielded per acre :— 
Straw, Grain. 
Tons cwt. qr. Ib. 
Manured con 2A als) OE BG ay; 3,481 lb., or 97 bushels of 36 Ib. 
Wnmanureds 28) 62 Se 2,810 lb., or 78 bushels of 36 Ib. 
Increase ... YB) pel oT 671 lb., or 19 bushels of 36 Ib. 
