[49] Flask still in my possession, unopened. *No. IX.--Turnip Infusion* remained for four days without undergoing any apparent change. Its neck was then accidentally broken at the fourth joint--a certain amount of fluid still filling the third joint. In this condition the flask was allowed to remain in the water-bath, and the fluid continued quite unchanged in appearance for five days. It was then boiled[50] for three minutes, and the neck of the flask was _hermetically sealed_ whilst the fluid was boiling. The flask being re-immersed in water-bath, the fluid continued quite clear for thirteen days. Its neck was then carefully heated in the spirit-lamp flame till, when red-hot, the rapid inbending of the glass showed that the vacuum was still preserved. This being ascertained, the flask was, after a few minutes, replaced in the bath. The next day the temperature of the bath was allowed to go up to 100° F. for three or four hours, and in the evening the fluid was observed to be very slightly turbid. In two days more (_i.e._, after sixteen days _in vacuo_) the turbidity was well marked, and when the fluid was examined microscopically it was found to contain an abundance of very languid _Bacteria_ and _Vibriones_. On opening the flask there was an outrush of very fœtid gas, and the reaction of the fluid was acid.[51] [50] The vapour had lost all odour of turnip. Some of the fluid which splashed over was found to be still slightly acid. [51] This experiment is very interesting in two or three respects. A neck of half the usual length--with only four bendings--sufficed to preserve the fluid for several days; and when this fluid (which had been in the bent-neck apparatus for nine days) was sealed up in the same flask during ebullition, it remained _in vacuo_ for thirteen days without undergoing any apparent change, and then only became turbid under the influence of a higher temperature. Yet some of the same fluid, in a flask which was hermetically sealed during the first ebullition (No. XV.) behaved as such an infusion usually does, and became quite turbid in forty-eight hours. _d. Fluid in a Flask having a Neck two feet long, bent at right angles shortly above the bulb, and provided with a firm Plug of Cotton-Wool twelve inches in length._ *No. X.--Urine* remained quite bright and clear during the fifteen days in which it was kept under observation in the water-bath.[52] *No. XI.--Hay Infusion* showed a very slight amount of sediment after forty-four hours, which seemed to increase somewhat during the next three days. The fluid afterwards appeared to undergo no further change, though it remained in the warm water-bath for fifteen days.[52] *No. XII.--Turnip Infusion* in four days showed a well-marked turbidity, and also very many flakes of a broken pellicle.[52] [52] Flask still in my possession, unopened. _e. Fluid (in vacuo) in a Flask, the Neck of which was hermetically Sealed by means of the Blowpipe Flame during Ebullition._