78 REPORT 1842. 



of evaporation in water-dressing. This valuable addition to therapeutics was chiefly to 

 he ascribed to Dr. Macartney, who was really the first, and not the Germans, to point 

 out its utility, and to explain its pathological action ; but, independent of water-dress- 

 ing, oiled siik proved, simply by itself, of great value as a therapeutic agent, by pre- 

 serving parts to which it is applied from changes produced by the atmosphere, by pre- 

 venting evaporation, and thereby promoting perspiration and a return to healthy 

 action. This was found to he particularly the case in dry scaly affections of the skin, 

 which in mild cases its use completely removed, as in slight attacks of psoriasis, lepra, 

 and scaly affections of the scalp. He had also found it useful as a derivative, removing, 

 when worn on the head, obstinate chronic ophthalmia and protracted coryza. Its use 

 in water-dressing was well known, and extensively practised ; but he found it equally 

 valuable where it was necessary to use more active agents, metallic salts, in solution 

 for different purposes : these lotions it materially improved in cases of severe eczema 

 and prurigo. 



He had found another application of air-tight textures of great use, to assist the 

 operation of derivants or revulsives applied to the external surface. For this purpose 

 Mackintosh's India-rubber cloth answers best. Flannel or cotton cloths dipped in 

 hot water, when covered with a piece of this cloth, act as a poultice or fomentation, 

 and are very beneficial in slight inflammations of the chest or abdomen. By adding 

 salt, mustard, ammonia, turpentine, or various other stimulants to the water, a counter 

 irritant operation is added, which the superimposed air-tight cloth renders more equal 

 and durable than that resulting from any common counter irritant. Such applications 

 Dr. W. has found very serviceable in phthisis and other chronic affections of the 

 chest. 



A third therapeutic use of air-tight cloth was one invented and lately made with 

 sucoess by Dr. Arnott, as a means of applying equal pressure to parts : this was by 

 using a slack air-cushion or bladder containing a little air between tho bandage or 

 compress and the part to be pressed on. This interposed a layer of uir, which dif- 

 fused the pressure equally and softly. 



On the Influence of the Coronary Circulation on the Heart's Action. 

 By J. E. Erichsen. 

 The influence of arterial blood on the voluntary muscles, the author stated, was ac- 

 knowledged by physiologists ; and surgeons were familiar with the fact, that when the 

 main artery of a limb, as the femoral or axillary, was tied, the contractility of the 

 muscles of the extremity was much impaired, and was not restored until the complete 

 reestablishment of the circulation. We ought then, a priori, to expect that a similar 

 influence would be exerted over the involuntary muscles, particularly over the heart. 

 Dr. Marshall Hall, in his Gulstonian Lectures, attributes sudden death frequently to 

 an interruption of the coronary circulation. From the importance of the subject, in 

 a pathological view, Mr. Erichsen undertook a series of experiments to demonstrate, 

 as far as possible, the influence of the coronary circulation on the heart's contractility. 

 These were numerous and varied. The coronary vessels were tied after killing the 

 animals, artificial respiration was kept up, and the time the heart, in its several parts, 

 continued to contract was accurately noted ; each experiment was detailed, and the 

 following conclusions Mr. Erichsen deems fully established : — First, that an arrest of 

 the coronary circulation produces a speedy, although by no means instantaneous, ces- 

 sation of the heart's action. Second, that an increase in the quantity of blood sent 

 into or retained in the muscular fibre of the heart, produces a corresponding increase 

 in the activity of the organ. The latter deduction was made from experiments in 

 which the aorta was tied, thus causing a greater quantity of blood than natural to be 

 forced into the coronary artery ; artificial respiration was not kept up ; the right ven- 

 tricle continued acting for a much longer time than it would do, under similar cir- 

 cumstances, when no ligature was applied to the aorta. In connexion with this ex- 

 periment the following fact was observed : — that the order of cessation of the different 

 cavities of the heart was reversed. In it the order of cessation was as follows : — First, 

 the left ventricle ; second, the right auricle ; third, the left auricle ; fourth, the right 

 ventricle. It has been established by Haller and subsequent physiologists, that the 

 right auricle acts longest in ordinary death, and was therefore denominated the 

 M ultimtm mortem" 



