Popular Science Monthly/Volume 27/June 1885/Use of Sulphurous Disinfectants
|USE OF SULPHUROUS DISINFECTANTS.|
AMONG the most convenient and efficacious substances to be used for purposes of disinfection are sulphurous acid and bisulphide of carbon. The question of the merits of these substances and the advantages of using them was recently considered, in the "Journal de Pharmacie et de Chimie," by M. Alfred Riche, who said: "M. Dujardin-Beaumetz recently requested the concurrence of MM. Pasteur and Roux in instituting new experiments on the value of disinfectants, and has just published the results of the same in the 'Bulletin' of the Academy of Medicine. Two rooms of about a hundred cubic metres capacity were selected in the wooden barracks attached to the hôpital Cochin. The walls of these rooms, made of jointed planks, gave passage to the air through numerous cracks, although the precaution had been taken of stopping the larger ones with paper. Each of the rooms was furnished with a bed, the usual furniture, and cloths of different colors. Bromine, chlorine, and sulphate of nitrosyle were successively rejected. Three sources of sulphurous acid were experimented upon — the combustion of sulphur, liquefied sulphurous acid, and the combustion of bisulphide of carbon. The room was closed for twenty-four hours. Tubes containing culture-infusions sowed with different proto-organisms, especially the comma microbe described by Koch, were placed in rooms, together with tubes containing vaccine lymph. After each experiment the tubes were taken to M. Pasteur's laboratory, and there compared with other tubes used as tests. The process of the combustion of sulphur is the simplest and cheapest. To perform this combustion, it is sufficient to set on the floor a sheet-iron plate — a large potsherd on the ground gives a satisfactory result on which is placed a furnace of bricks and mortar, or better, one of those small, nearly square furnaces of fire-clay recommended by M. Pasteur, twenty-five centimetres long and twenty centimetres wide, and having the sides pierced with air-holes. To obtain a complete combustion of the flowers of sulphur, it is necessary to
take care that the whole surface be evenly burned; this may be effected by wetting the sulphur with alcohol and inflaming the alcohol. By this method we can burn completely and absolutely as large a quantity as forty or fifty grammes per cubic metre of flowers of sulphur. With twenty grammes per cubic metre, all of the culture-infusions experimented upon were sterilized, except the one containing the carbuncular (anthrax) bacteria. The activity of the vaccine virus was destroyed. The only probable inconveniences involved in the application of this economical process arise from the danger of fire in case the furnace is badly constructed, and from the liability of the metallic objects that may be present to be tarnished. This may take place from particles of the burning element flying around the room, and, settling on articles of copper and iron, covering them with a sulphurous coating.
"The process of using liquid anhydrous sulphurous acid in siphons is free from these inconveniences. The siphons contain 750 grammes of the acid, and one of them is efficient for the disinfection of twenty cubic metres of space. In using the siphons a vessel is set in the middle of the room, and is put in communication with the outside by means of an India-rubber tube passing through a hole in the door. The door having been closed, the orifice of the siphon is inserted into the India-rubber tube, and, the liquid being let in through it, is freely evaporated in the air of the room. This process is very convenient; it avoids the danger of fire, and does not affect metallic objects; and the penetrative force of sulphurous acid thus administered appears to be greater than that of the acid obtained by burning sulphur. The only drawback to its use is the high cost. The siphons are sold to the general public for a dollar each, but can be bought in large quantities
for half that price. Thus the expense of disinfecting a room of one hundred cubic metres with this preparation would be from two and a half to five dollars."
The process of the combustion of bisulphide of carbon was suggested by M. E. Peligot; and all danger in employing it is obviated in the new burner invented by M. Ckiandi Bey, engineer. This apparatus is illustrated, with a view of its interior arrangement, in Fig. 2; and a more detailed explanation of its parts can be obtained from the examination of Fig. 3.
M. Ckiandi's burner is composed of an exterior receiver of tinned copper, A B C D, containing an interior vessel, I H E F, to the sides of which are fixed three siphons, R S. To put it in operation, the cylindrical tube, K L M N, is placed in the interior vessel; sulphide of carbon is poured in up to the level a a, and the exterior receiver is then filled with water up to the level b b. By means of the siphons the water
penetrates into the interior vessel, presses upon the sulphide of carbon, which is heavier than it, and drives it in the interior tube up to the level a' a', where it is taken up by a cotton wick, which is lighted. The upper end of the tube is crowned with a chimney, P Q, to facilitate the draught. The combustion of the sulphide of carbon may be increased or slackened at will by raising or lowering the level, b b, of the water in the external receiver; and this facility will be found of advantage in many cases.
The burner is placed in the room to be disinfected and lit, when the room is evacuated and shut up tight. When all the sulphide of carbon has been burned, its place is taken by water, and the lamp goes out of itself; in the mean time the burning goes on with great regularity, and without any danger. About two and a half kilogrammes (six and a quarter pounds) of sulphide of carbon are sufficient for a room of a hundred cubic metres. The process is effective and economical enough; for sulphide of carbon is sold commercially for fifty centimes (about ten cents) per kilogramme, which gives about twenty-five cents as the price of disinfecting a room of a hundred cubic metres. The burner costs ten dollars, but it will last for a very long time. This process is evidently practicable and convenient. It does not tarnish metallic objects, and furnishes a continuous, slow, and regular disengagement of the disinfecting gas. Translated for the Popular Science Monthly from La Nature.