OF TREATMENT IN SURGERY 71 



kinds of emplasira ; but these appeared objectionable on account of their ad- 

 hesiveness, which is greatly increased by the admixture of carbolic acid, and 

 which seemed likely to be mischievous by retaining the discharge. I next 

 employed paraffin, mixed with a little wax to give it tenacity, and a little 

 olive oil to confer the requisite softness. This certainly made, under ordinary 

 circumstances, an effective as well as elegant substitute for the putty, being 

 perfectly devoid of adhesiveness, while a comparatively thin layer proved 

 securely antiseptic. But the paraffin cerate had this great disadvantage, 

 that, in situations where it was subjected to much movement, such as the groin, 

 it was apt to crumble down and become useless. Meanwhile I learned that 

 Dr. Watson, of Edinburgh, was employing soap-plaster mixed with carbolic 

 acid, and that, though adhesive, it appeared to work well ; the discharge finding 

 its way out beneath it. Thus I was again induced to try emplastra ; and of late 

 we have been using what seems to answer admirably, namely emplastrum plumhi 

 mixed with one-fourth part of bees-wax to give it sufficient consistence, the 

 carbolic acid being in the proportion of about one-tenth of the whole.^ This is 

 used as a plaster spread on calico in a layer of about one-twentieth of an inch 

 thick, and I can recommend it as thoroughly reliable. There is a case which 

 I am dressing with it at the present time, which I may mention on account of 

 its interest otherwise. 



Case of Old Fracture at the Ankle with Fixed Displacement of the Foot, Rectified 



* In making the plaster with the ingredients mentioned in the text, the emplastrum plumhi and 

 the bees-wax are melted and mixed together, and allowed to cool, till the liquid begins to thicken ; the 

 carbolic acid is then added and stirred in, which has the effect of bringing back the mass into the state 

 of a thin liquid, which is assiduously stirred till it thickens, to prevent the wax from separating in 

 granules. This plaster is, however, inconveniently soft, and cannot be kept spread in stock. I have 

 since found that by increasing the proportion of litharge, the lead soap may be made of any degree 

 of firmness that may be desired, provided that water be not used in the manufacture. When the 

 litharge and olive oil are in the proportions directed by the Pharmacopoeia, a certain quantity of water 

 must be added to promote the combination of the fatty acids with the oxide of lead, and even then the pro- 

 cess is a very tedious one. But it is an interesting fact chemically, that if the litharge is used in about four 

 times the pharmacopoeial proportions, although no water be employed, the combination proceeds under 

 a brisk heat with great rapidity. It is upon this fact that the follo%ving method of manufacture is based : 

 Take of olive oil, 12 parts by measure; litharge (finely ground), 12 parts by weight; bees-wax, 

 3 parts by weight ; crystallized carbolic acid, 2\ parts by weight. Heat half the oil over a slow 

 fire ; then add the litharge gradually, stirring constantly till the mass becomes thick or a little stiff. 

 Then add the other half of the oil, stirring as before till it becomes again thick. Tlien add the wax 

 gradually till the liquid again thickens. Remove from the fire and add the acid, stirring briskly till 

 thoroughly mixed. Cover up close and set aside, to allow all the residual litharge to settle ; then pour 

 off the fluid, and spread upon calico to the proper thickness. The plaster made in this way can be 

 spread by machine, and kept rolled up in stock ; and, if in a well-fitting tin canister, will retain its 

 virtues for any length of time. This I believe to be the most perfect form in which an antiseptic lead- 

 plaster can be obtained. For almost all purposes, however, it is superseded by the lac-plastcr, which 

 will be found described in the succeeding part of this address. These improvements in the materials for 

 dressing have occupied a much longer time than I had anticipated ; and have been the cause of the 

 delay in publication. — J. L. 



