In the proportion of 8 grains to the cubic foot, all the different culture broths under experiment were sterilized save the one containing the bacteria of charbon. As for the vaccine virus, its properties were destroyed. This economical process presents but two inconveniences, viz., the possibility of fire when the furnace is badly constructed, and the alteration of such metallic objects as may be in the room. In fact, the combustion of sulphur is attended with the projection of a few particles of the substance, which form a layer of metallic sulphide upon copper or iron objects. [Illustration: FIG. 2.--CKIANDI BEY'S APPARATUS FOR BURNING CARBON SULPHIDE.] The use of liquid sulphurous acid in siphons does not offer the same inconveniences. These siphons contain about one and a half pounds of sulphurous acid. The proportion necessary to effect the sterilization of the culture broths is one siphon per 706 cubic feet. In such a case the _modus operandi_ is as follows: In the middle of the room is placed a vessel, which is connected with the exterior by means a rubber tube that passes through a hole in the door. After the door has been closed, it is only necessary to place the nozzle of the siphon in the rubber tube, and to press upon the lever of the siphon valve, to cause the liquid to pass from the siphon to the interior of the vessel. The evaporation of the liquid sulphurous acid proceeds very rapidly in the free air. This process is an exceedingly convenient one; it does away with danger from fire, and it leaves the gildings and metallic objects that chance to be in the room absolutely intact. Finally, the acid's power of penetration appears to be still greater than that which is obtained by the combustion of sulphur. It has but one drawback, and that is its high price. Each siphon is sold to the public at the price of one dollar. To municipalities using sulphurous acid in this form the price would be reduced to just one-half that figure. It will be seen, then, that for a room of 3,530 cubic feet capacity the cost would be $5.00 or $2.50. The combustion of sulphide of carbon furnishes an abundance of sulphurous acid, but has hitherto been attended with danger. This, however, has recently been overcome by the invention of a new burner by Mr. Ckiandi Bey. The general arrangement of this new apparatus is shown in Figs. 2 and 3. Mr. Ckiandi's burner consists of an external vessel, A B C D. of tinned copper, containing a vessel, I H E F, to the sides of which are fixed three siphons, R, S. [Illustration: FIG. 3.--SECTION OF THE APPARATUS.]