102 AGRICULTURAL REPORT. 
future demands. There are silicates of lime and of iron, of alumina, 
and of potash in abundance, and the caleareous matter is in ample pro- 
portion, not requiring addition even during fall-cropping over many 
years. It is remarkable that the lime carbonate seems to be wholly due 
to the presence of the shields or shells of the fresh-water ostracoid 
cypris, which exist in considerable numbers in the clay, and which may 
be readily exposed by elutriation. The existence of this recent Ento- 
mostracan points to the existence of large beds of fresh water at no 
distant period, covering up this district, and as all the samples of clay 
abound in this shell, the probability is that the inland sea extended to 
the very lower slopes of the Sierra Nevada, of which sea the present 
lakes scattered along the base of the Sierra are representatives. A1- 
though the presence of carbonate of lime is not indicated in any min- 
eral form, but apparently only existing in the shell of the cypris, yet it 
is obvious that this animal secreted it from out of some salt of lime in 
Solution in the waters of that time. The perfect condition of the shell 
indicates that it had its origin in its present habitat, and the conclusion 
is, therefore, that at some not far distant period the surface of this 
region was covered by an extensive inland lake. One of the facts ex- 
hibited by the analysis is the unusual amount of matters soluble in 
water which exist in these soils, being: No. 1, 4.59 per cent.; No. 2, 
7.03 per cent.; No. 3, 8.75 per cent. These proportions of soluble saline 
matters are so much in excess of what is found in ordinary soils that 
they demand investigation into the cause. In fertile soils, in well- 
watered districts, and where there is an abundant fall of rain, the 
soluble saline matter rarely amounts to one-half of one per cent., (0.5,) 
and more commonly ranges around one-quarter of one per cent., 
(0.20-0.33.) Professor Anderson, in his Elements of Agricultural Chem- 
istry, gives a few examples of the proportion of soluble salts in rich 
Scottish and other soils, viz: 
Soluble matter in surface soit. 
LUE i iGo: 4. So ar ai aM RRSP rs GMCS hE Ml fe 0. 2319 
BBE DMGHING wees cee cee ean baie oe oak chee he wee ee ee eee oo Bn a ae ene 0.1191 
USP PAT DEA sae. cae ctu... ecole eee Co oe ee eee 0. 3700 
> SS 
In the many analyses of soils made in this laboratory, the soluble 
Saline matter has never reached one-half of one per cent. It is to be 
regretted that a uniform method of analysis has not been adopted by : 
chemists for the analysis of soils, one of the features of which should 
show the per centage of soluble salts. The experiments with lysime- 
ters do not supply this needed information. It would not be hazarding 
a misstatement to declare that the poorest of these soils in soluble mat- 
ters contains eight times as much as fertile soils need, and No. 3 con- 
tains fifteen times as much. ' 
Another point of peculiarity in these soils is the amount of sodinm 
chloride (common salt) present, it being from three-fourths to four-fifths 
of the whole soluble matter. ‘his is far in excess of any usual propor- 
tion, and of what is needed. In the Antigua soil, already mentioned, 
the chloride of sodium did not exceed 0.09 in 100 parts. In many of 
Sprengel’s analyses, as quoted by F. W. Johnston in bis Agricultural 
Chemistry, the proportion lies between 0.06 and 0.009. In no.case has 
it appeared to reach one-tenth of one per cent. In limited sections of a 
country where tidal or salt-marsh water has opportunity to settle and 
develop vegetation having a necessity for salt, the amount of that min- 
eral in specimens of the, soils may have a much larger amount. Thus, 
