30 British Association for the Advanconent of Science. 



the same ingredients as those found in the lungs of the workman. 

 Dr. Gregory found in the stone carbonate of hme, sihca, and alu- 

 mina. The deduction must necessarily be, that this (pointing to 

 a preparation of the lungs which he exhibited) must be an abso- 

 lute deposition of the Craigleith-quarry stone, from small particles 

 taken into the lungs during respiration, producing consumption 

 and death. Dr. Macartney had seen many black glands at the 

 root of the lungs, and dispersed through its substance, but they 

 were not hard. It was stated that fibrous concretions in the 

 chest were rare ; this did not accord with his observations. In his 

 museum, at Trinity College, he had placed many examples' of 

 this disease. The inflammation gave, first, condensed lymph, 

 changed it into fibrinous, converted it into cartilage, and finally 

 into bone. Dr. Macintosh replied in the negative, to the question 

 if any other part of the body contained stone. 



Variations of Pressure on the Human Body. — Sir James Mur- 

 ray presented to the Section an apparatus for the purpose of with- 

 drawing atmospheric pressure from the surface of the body, par- 

 tially or wholly. He presented his reasons and observations to 

 the Dublin Medical Section of the British Association, but they 

 were not well understood, for want of apparatus and drawings. 

 These he had now got, which, besides much labor and time, had 

 cost upwards of 1001. ; and he trusted, since he was becoming old, 

 some of the Members would perfect them. The first machine 

 was for the whole body, and resembled in form a slipper-bath, 

 with the addition of a separate part to cover the upper portion of 

 the body, the head only being free. The upper portion was luted 

 to the lower, by means of a composition (used in making printers' 

 rollers for inking the types, ) and fixed in a groove ; and, if neces- 

 sary, the patient's face and head could be contained in a glass 

 case, luted to the machine in the same manner, and respiration 

 carried on by a tube. The air from the machine was removed 

 by means of an exhausting syringe, screwed on towards the bot- 

 tom part of this apparatus. He had tried this machine in the col- 

 lapsed cases of cholera, and exhausted the air from the body, ta- 

 king off" one ton of atmospheric pressure. The consequence 

 was, that the vessels became full and turgid, and the body, pre- 

 viously shrunk, was rounded and red. He had tried it repeatedly, 

 and the same results followed. The process might be reversed, 

 and pressure of air made on the body, even to the amount of 



