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EXPERIMENTS WITH SALINE SOLUTIONS 249 
The Solutions employed and the Results of 
theer Examination 
I restrict myself here to the mention of those 
saline solutions whose employment in my experi- 
ments have yielded more or less uniformly positive 
results. They are variants of the solutions already 
referred to as having been experimented with in 
1871-72, in reference to the question whether silicon 
could or could not replace carbon in the constitution 
of protoplasm. For the present it need only be 
noted that in the solutions themselves carbon did 
not exist, except it might be in the form of some 
impurity contained therein—either in the distilled 
water, or in one or other of the chemicals employed. 
In each case, however, silicon was provided and 
present, in order that it might possibly take the 
place of carbon in any organisms that appeared in 
the solutions. 
The first solution dealt with was one containing 
sodium silicate, ammonium phosphate, and dilute 
phosphoric acid. At first these ingredients were 
used in the proportion of six drops each of the 
first and third, and six grains of the second to the 
ounce of distilled water. Later, after some com- 
parative trials with different strengths of such solu- 
tions, each of which was inoculated with Bacteria, 
simply to test the relative virtues of the solutions 
as mere ‘‘nourishing” fluids, | was induced to use 
four drops and four grains, in the place of six, 
to the ounce of water. In each case this gave 
