30 ~—s British Association for the Advancement of Science. 
the same ingredients as those found in the lungs of the workman. 
Dr. Gregory found in the stone carbonate of lime, silica, 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 find drawings. 
These he had now got, which, besides much labor and time, had 
cost upwards of 100/. ; 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 ina 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 re 
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 — results followed. The process might be reversed, 
and pressi re of air made on the body, even to the amount of 
