Page:The Liquefaction of Gases.djvu/78

74 though at first it seemed rather deeper. A moist vapour, coating the inside of the receiver, arose upon the compression of the hydrogen, which moisture was strongly acid to the taste, coloured litmus, and, when very much diluted with water, acted upon silver.

Nearly the same as the last, but with different arrangement. The nitrogen, three pints and a half, was first introduced; then the hidrogen, two pints; and next the oxigen, three and a half. The nitrogen formed the orange-red colour as before; the hidrogen produced white clouds at first (quœre ammonia?) which afterwards disappeared, and the orange-red colour became lighter; but upon the affusion of the oxigen, the colour did not disappear as in the last experiment, but, if any thing, became darker. I then injected two pints more of hidrogen, but this had little or no effect upon the colour. Some vapour was generated, which was, as usual, strongly acid.

Previous to the bursting of the small receiver, I had put in it a scruple of lime, and condensed upon it three pints of nitrogen. The result was, a little reddish colour at first, which soon vanished. Upon repeating this experiment in the large receiver, I could produce no colour at all. In my present state of knowledge I am unable to account for this circumstance; but as soon as I get my new receivers of a smaller capacity, I mean to repeat the experiment.

Besides the above, I have made various other experiments with different gases, but I think it right to repeat them with greater accuracy before I submit them to the