2 Bouyoucos, Transpiration of Wheat Seedlings as Affected etc. 
Review of Literature. 
The literature bearing directly upon this part of the investigation is rather 
limited, considering the importance of the subject. Of the most important 
works reported on the subject may be mentioned the following: 
a 
Bur gerstein 1 ) in his investigation upon the transpiration of plants, 
studied also the effect of different densities of Solutions of Ca(N0 3 ) 2 , KN0 3 , 
K 2 HP0 4 , K 2 C0 3 , NH 4 H0 3 , (MH 4 ) 2 S0 4 , and other Chemicals. He found 
that transpiration increased with the' increase in density of all these single salts 
up to a certain point, above which it began to decrease. 
Schroeder 2 ) found that the amount of water transpired, per unit of 
dry matter produced increased w*th the concentration of the nutritive material 
present, up to a certain density, beyond which' it feil. 
Sorauer 3 ) grew plants for eight weeks in a nutrient solution of different 
concentrations. He found that the relative transpiration decreased with the 
increase in concentration. 
Heinrich 4 ) studied the amount of water transpired by oats in a complete 
nutrient solution of different strengths. He found that transpiration decreased 
per unit of dry matter, with the increase in concentration. 
Maercker 5 ) grew white mustard in an artificial soil, contained in zinc 
pots. He added to the soil different amounts of moisture and various quantities 
of Kainit and Carnallite, and studied the effect of these salts upon the amount 
of water required to produce a given quantity of dry substance. He failed to 
seal the pots to prevent the direct evaporation from the surface of the soil, but 
the results he obtained go to indicate that the application of the potash salts 
produced a distinct economy in the absorption of water, and this was more 
marked in the lower than in the higher moisture contents. 
Kiesselbach 6 ) grew corn for two and a half months in pure river 
sand watered with a complete nutrient solution. His results show that the 
amount of water transpired per gram of dry matter, tends to increase with the 
. decrease in density. 
General Methods of Investigation. 
In the present work the effect of the different densities of 
solution upon the transpiration of plants, was studied in water, 
sand and soil cultures, at the same time and under the same con- 
ditions. 
The water cultures were prepared and conducted according 
to the methods recommended by the Bureau of Soils 7 ), with a few 
modifications. 
4 ) Sitzungsber. Akad. Wiss. Wien. Math.-Kat. CI. Bd. 83. 1876. p. 191. 
2 ) Anw. Inst. Agr. Moscow. 2. 1896. p. 188—226. 
3 ) Allgem. Brauer- u. Hopfenzeitg. 23. 1882. p. 15—19. 
4 ) 2. Ber. Landw. Vers.-Stat. Rostock. 1894. p. 170—174. 
6 ) Arbeit. Landw. Ges. H. 20. 1896. 
6 ) Nebraska Agr. Expt. Sta. 23rd. Ann. Rept. 1910. p. 138. 
7 ) Bull. 23, Bureau of Soils, U. S. Dept. of Agr. 1904. 
