IM STATE BOARD OF AGRICULTURE. 



T. The cliemical analysis. 

 II. Tlie pliysiological analysis. 



A cliemical analysis seeks thronjili its results a detennination of soil 

 fertility. However, one can not claim that this method has been es- 

 pecially successful. The only thino- which we can say with surety about 

 its results is that if a cerlain nutritive element is found to be absolutely 

 not iiresent in the soil, then it is lacking for the nutrition of the ])lant. 

 The dilficult ]»roblem concerning the relation between chemical analysis 

 and availability slill awaits solution. 



The jthysiological analysis draws its conclusions from the vegetation 

 itself. In other words, it is an attempt to put direct observation in 

 the place of theoretical deduction. Since no definite results from the 

 analysis of the soil solution have been so far obtained, and since one 

 must recognize that the latter has no scientific value as a determination 

 of soil fertility, the author has applied not only chemical analysis to the 

 solution but in connection with this also a physico-chemical analysis. 



We may suppose from analogy that the physico-chemical analysis of 

 such a liquid may be of exceptional value. However, I must emphasize 

 that in spite of all the various determinations I do not feel myself called 

 upon to draw any definite conclusions from these analyses with refer- 

 ence to the exceedingly complex question of soil fertility. So far as 

 chemical analysis is concerned, we must keep before ourselves the all 

 important fact, ^'corpora non agunt nisi soluta," in other words, that 

 only which is j)resent in the soil solution can be taken up as a nutritive 

 substance, but not everything present need be taken up. 



There still remain a fcAV things which I should like to say. I will 

 state the facts that were revealed by the application of our method. 

 Complete results will appear in a publication of the near future. 



This is not the place to discuss the details of the different analyses. 



(1) In many cases there was found in the soil solution a slime. 

 This must be regarded as the first experimental proof of the presence of 

 this substance in soil, and it is not im])ossib]e that much of the irregular 

 behavior of the life in soil could be explained to some extent wnth a 

 knowledge of this slime. If I may be peniiitted, I should like to call 

 your attention to the possibility of this substance having an effect on 

 desiccation, diffusion, and other processes. 



(2) The specific gravity of the soil solution which influences the 

 movement of the soil water was found to be higher than that of water, 



(3) As to the viscosity of the soil solution which governs to a certain 

 extent the rate of adjustment of soil water in the soil, we can say that 

 it is relatively' high. 



(4) The sui'face tension, a ]ir(»perty of liquids which is associated 

 with adsorption and has an inlluence on the degree of capillarity, was 

 fomid to 1»e distinctly low in the case of the soil solution. 



(5) In reference ito the osmotic pressure of tlie soil solution, which 

 on one hand is the indicator of the state of solubility, and has a bear- 

 ing on the adjustment of the water in the soil, and on the other hand 

 Tiiarkcdly inllucnces the lif(^ in the soil, we can say that this pressure is 

 low, a result which was to be expected from the comparatively high 

 resistance of the liquid. 



(fi) Another thing noticed is the atid and l>;isic binding capacity. 

 This was found bv the electrotitrimetric method. In general we may 



