FUMIGATION. The vapours of hot vine gar, burning sulphur, and of aromatic vege table matters, have been long used to coun teract unpleasant or unwholesome smells : this is effected chiefly by the formation of such as are stronger. The most important kind of fumigation is that which consists in the employment of such vapours or gases as do not merely destroy unhealthy odours by exciting such as are more powerful, but which by their chemical action prevent the de composition of' animal and vegetable matters.
The fumigation of the first kind, that which is intended to produce a healing effeet,is now much less employed than formerly: IA the last kind of fumigation several substances have been employed in the gaseous state ; such as the vapour of burning sulphur, or sulphurous acid gas, muriatic acid gas, nitric acid gas, and chlorine gas. Chlorine which is undoubtedly preferable to any disinfectant, was first recommended by Dr. Rollo, the gad being liberated by the usual method of mixing sulphuric acid, binoxide of manganese, aril common salt. When it is desirable to pro duce a great effect in a short time, this id still unquestionably the best mode of pro ceeding.
Where unpleasant smells or effluvia are Produced only in small quantities, the chlo ride of lime or soda, and especially of the former, has been within a few years success fully employed. The chloride of lime is a sub stance well known and extensively employed under the name of bleaching powder. It is used in solution, and is obtained by dissolving one part of Bleaching Powder in about 100 times its weight of water, and allowing the so lution to become clear. This is to be exposed
to infected air, or, in rooms which have any unpleasant odour, in flat vessels, in order that a sufficient surface maybe acted upon. If it should be required, the operation may be quickened by the addition of a little vinegar, or of muriatic acid largely diluted.
Where it is necessary to diffuse a gas, va pour, or smoke over a given space, the usual plan is to place some easily evaporable sub stance on or near the spot ; but in fumigating plants some difficulty arises. To remove this difficulty is the object of Brown's Fumigator, an ingenious apparatus patented in 18-19. It comprises a cylinder, a fan, a funnel, a handle, a winch, and a spout. The cylinder is a me tallic chamber, across the centre of which an axle extends ; and to the middle of this axle a fan of Several vanes is attached. The winch, outside the cylinder, affords the means of giv ing a rapid rotatory movement to the vanes; while a handle on one side of the cylinder enables the apparatus to be conveniently held in any desired position. The funnel is fixed into the top of the cylinder, and has a dia phragm of perforated metal about its centre. The action of the apparatus is simply as fol lows. Tobacco or other substance whose ftimes are required, is put in the funnel and ignited, and the top of the funnel closed; the winch is turned, and the draught thereby oc casioned within the cylinder sucks in the smoke, and then forces it out through the spout. This spout is so formed as to act easilytn any part of a plant.