The: Fixation of Nitroge;n. 8i 
bad and has slowly grown worse during the time that I have had 
it under observation. 
It may be wise to state that it is not intended that any one 
should infer that I doubt the value of drainage in removing ex¬ 
cessive water from land, but simply to state that at the present 
time I do not believe that we have much reason to hope for any 
material relief from this trouble by drainage, even in cases of 
comparatively low lands, while it is wholly out of the question in 
cases of high or naturally well drained lands. If these lands could 
be kept covered with water to a depth of several inches, twelve or 
more, for a number of days and then be thoroughly drained out 
the aerobic bacteria might in this way be killed off and the excess 
of nitrates removed; but this could be applied to small and favorably 
located areas only; the costs would be heavy and the permanency 
of any benefit doubtful. This, however, has not yet been tried. 
Cases Nos. 8 and 24 of this bulletin and No. 3 of Bulletin 155 
pi esent the facts relative to what we may hope from flooding or 
persistent washing of the soil more fully than any others that have 
come under my observation. Case No. 8 is particularly instructive 
because the drainage is apparently perfect and it received twelve 
profuse irrigations in the season of 1909, and yet in 1910 the 
puffed and mealy condition of the soil was as bad as I had ever 
seen it and the surface soil was very rich in nitrates. The effort 
made in 1909 to wash out this soil was apparently futile, and we 
have shown by analyses of the soil, of alkali and of the ground 
water from adjacent lands that these nitrates do not come from 
these sources and the nitrates found in 1910 do not represent a 
resupply from this source. There is no question but that these 
niti ates can be temporarily washed out of the soil, but they were 
as abundant, if not more so, in 1910 than they were in 1909 when 
the land was irrigated twelve times in the endeavor to wash out 
the black alkali. I have presented in Case No. 24 an analysis 
of a sample taken in June which, as I take it, represents the salts 
present in the surface soil under ordinary conditions; also of a 
second sample taken in September, because this ground was 
flooded twice in the month of August, once to a depth of two feet 
which required 24 hours to flow or drain off. The easv solubility 
of the nitrates makes it a matter of surprise that we should find 
about a month subsequent to the last flooding not only so large 
an amount of soluble salts but also so large a quantity of nitrates 
present. Case No. 3 was given in Bulletin 155; in this case the 
owner had tried for 16 years to bring these spots under subjec¬ 
tion ; he had plowed and flooded, but without success. I have not 
as yet seen or learned of any result obtained by flooding which 
gives any solid basis for expecting very permanent, beneficial re- 
