W. YOUNGMAN 149 
This removal of bags from the small dessicators continued at weekly 
intervals. The germination tests were carried out as follows. The method 
is the one recommended by Schénfeld in Wochensch Brau, 1902, 19, 768. 
A wooden stand containing a line of small glass funnels was fitted up. In the 
apex of each funnel a small plug of glass wool was placed. A short length of 
india-rubber tubing provided with a pinch cock was attached to the stem of 
each funnel. The barley was placed on the glass wool and then flooded 
with water for about five hours. The water was then run off by opening 
the pinch cock and the barley left alone for some 18-19 hours. At the end 
of this time the barley was again flooded for a second period of five hours. 
Two floodings were sufficient to start germination, and, with but few 
exceptions, all those grains that would germinate did so by the third day, 
very few lingered until the fourth, on which day the germinated grains 
were counted. The funnels were kept covered during the experiment 
with clock glasses. Observations of the maximum and minimum temperatures 
of the laboratory were made daily. The percentages of germinating grains 
are given in the table below. A set of estimations of the amounts of water 
vapour contained in samples of air exposed to solutions of sulphuric acid 
of the strengths used was then made. This was carried out in the 
following manner :— 
A series of four small wash bottles was fitted up and into each was put 
a quantity of sulphuric acid of the percentage under consideration. The 
intake tube of one bottle was connected with the exit tube of the bottle 
before it, and the intake tube dipped beneath the surface of the acid in its 
bottle. Air was drawn slowly through this series of four bottles containing 
the sulphuric acid. Connected to the fourth bottle was a U tube containing 
calcium chloride. This calcium chloride tube was in its turn connected to a 
second one, and this again to a third calcium chloride tube which was 
followed by anempty Utube. Through all these tubes and bottles a measured 
quantity of airwas drawn by means of an aspirator of 20,000 c.c. capacity. 
The air was drawn over very slowly, the whole 20,000 c.c. taking some five 
hours. The two calcium chloride tubes next the bottles containing the acid 
were weighed before and after the experiment. The third calcium chloride 
and the empty U tube also were simply to catch any water vapour passing 
back from the aspirator; they were not weighed. By this means we were able 
to estimate the number of grams of water vapour per litre contained in 
air over each particular percentage sample of sulphuric acid used. The 
following table gives the results :— 
