i82 THE ADDRESS IN SURGERY DELIVERED BEFORE 



than nothing. Let me say a word or two, in the first place, as to the principle 

 on which it is constructed. It appears that the best kind of spray which can be 

 produced is that which is formed on the principle of the atmospheric odorator, 

 by having one tube set at right angles to another, the air-tube being larger than 

 the water-tube, and the opening of the water-tube being exactly opposite the 

 middle of the orifice of the air-tube. This makes the finest and best of all sprays. 

 But, with a heavy apparatus like this, it would never do to have to move it 

 about along with the nozzle, as is absolutely necessary in the instruments of 

 ordinary construction on this principle. We must have tubes to convey the 

 air and the water to a considerable distance ; and this is very easily done by 

 not merely having the liquid ejected by the force of the air blown over the 

 orifice of the water-tube, but by having it driven through the tube by the force 

 of the same pump that propels the air, the quantity of the water being regulated 

 by a stop-cock. Then it was necessary to provide some ready means of clearing 

 the fine end of the water-tube, in case of its obstruction by particles of dust. 

 This is done by having the water-tube straight for a short distance from the 

 nozzle, and then bent at a right angle, with a little milled cap to screw on at 

 the angle, so that, in case of obstruction, the cap is screwed off, and the orifice 

 of the water-tube is cleared at once with a needle or a bit of fine wire. I have 

 used this apparatus in various operations of late, among which I may mention 

 my two last amputations, one in the thigh, the other in the arm, in both cases 

 using nothing stronger than the one to a hundred solution for the spray, and 

 the same for the sponges ; except only, what I believe to be a wise precaution, 

 that, when a sponge has become soaked with blood, it should be washed first 

 with pure water, then dipped for a moment in a strong solution (one to forty), 

 and then squeezed out of a solution of one to a hundred to give it the necessary 

 blandness ; and in both these cases putrefaction was entirely avoided. [The 

 apparatus exhibited had two nozzles, attached to independent caoutchouc 

 tubes, furnishing large clouds of spray, that could be directed, if necessary, to 

 opposite sides of the part operated on. Two of Richardson's spray-producers, 

 worked by two assistants, will answer the same purpose, though less efficiently.] 

 The antiseptic catgut ligature is used for securing the arteries while the 

 spray still plays over the wound. It is absolutely necessary that it should be 

 properly prepared. I must not enter into the method of preparation, further 

 than to say that catgut undergoes a remarkable change in its physical constitu- 

 tion when steeped for a long time in an emulsion of water and oil, so that it 

 becomes quite transparent, and no longer liable to become soft and slippery 

 when placed in water or in a watery discharge. But for this circumstance, 

 the animal ligature would be an impossibility ; but, if you use it properly pre- 



