MICHIGAN ACADEMY OF SCIENCE. 
69 
difficult problem between the relation of chemical analysis and avail- 
ability still awaits solution. 
The physiological 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 
reference to the exceedingly complex question of soil fertility. So far as 
chemical analysis is concerned w!e must keep before ourselves the all 
important fact, “corpora non agunt nisi soluta,” in other words that 
only which is present in the soil solution can be taken up as a nutritive 
substance, but not every thing present need be taken up. 
There still remain a few 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. 
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 impossible that much of the irregular 
behavior of the life in soil could be explained to some extent with a 
knowledge of this slime. If I may be permitted, I should like to call 
your attention to the possible effects of this substance on dessication, 
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 cer- 
tain extent the rate of adjustment of soil water in the soil, we can 
say that it is relatively high. 
(4) The surface tension, a property of liquids which is associated 
with adsorption and has an influence on the degree of capillarity, was 
found to be low in the case of the soil solution. 
(5) In reference to the osmotic pressure of the 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 
markedly influences the life 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. 
(6) Another thing noticed is the acid and basic binding capacity. 
This was found by the electrotitri metric method. In general we may 
say that the neutrality was obtained by adding very small quantities of 
a normal 1000° alkali or acid. 
(7) In regard to chemical analysis you will not be surprised to hear 
that all nutritive substances could be found in our soil solution to a 
certain degree. An astonishing fact, however, is the relatively large 
quantity of nitrites in some samples. With reference to the value of 
