TRANSACTIONS OF THE SECTIONS. 
95 
body on the application of cold. When the application is transient and 
the circulation vigorous, the contraction of the vessels and paleness 
of the surface are only momentary, and are succeeded by reaction 
evinced in increased heat and diffused blush of redness. When it is 
long continued, then the pale and shrunk state of the surface is gra¬ 
dually succeeded by a purple or livid colour, attended with increase 
of size, as may be proved by a ring on the finger, from the swollen 
state of the vessels. Comparing these facts with the experiments de¬ 
tailed by Dr. Alison,—which showed that in inflamed parts not only 
the small vessels but the large arterial trunks leading to the part are 
dilated, and rendered incapable of contracting like other arteries,— 
Dr. Osborne proposes the question, whether there is not sufficient 
evidence to prove that cold produces inflammation by producing 
torpor and dilatation of the vessels, either of the part itself or of 
some connected or adjacent part, which, if not removed by transient 
reaction, is followed by the more permanent reaction of inflamma¬ 
tion, causing a number of new phenomena. 
With regard to the effect of cold on the skin, which is the most 
important of all, it is evident that meteorology has contributed very 
little to our knowledge of the influences of the atmosphere on health 
or disease. It has appeared to the Author, that in order to connect this 
science with utilitv, as far as mankind is concerned, one considera- 
tion has been omitted, which is, the cooling power of the atmosphere 
estimated with reference to ourselves. The human body has a heat 
of nearly 98°, and is placed in a medium always cooler than itself. 
The degree of cooling influence exerted on it has never been made 
the subject of measurement, and to the present time is estimated 
solely by the feelings. In order to measure the cooling influences 
of the air or other media, Dr. Osborne used a spirit thermometer, 
without a frame, carefully graduated from the degree 90 to 80 in¬ 
clusive, that being nearly the temperature of the exterior of the body. 
Having heated the bulb to 90°, he exposed it in different situations, 
observing the time during which the spirit descended from 90° to 80°, 
and adopting, as a measure of the refrigerating power, the rate of 
cooling deduced. And by this contrivance is exhibited the result 
of radiation, and of the conducting power of the atmosphere as 
modified by its temperature, its density, its moisture, and its cur¬ 
rents; and that result, the most interesting of all to the invalid, 
who, in respect to temperature, may be conceived as represented 
by the instrument. As the variety in the shape of the bulb, the 
bore of the tube, the thickness of the glass, or the density and 
quantity of the fluid employed will cause variety in the time of the 
descent, the result obtained with two thermometers must not be ex¬ 
pected exactly to correspond. In order to procure uniformity for 
this purpose, it will be necessary to place a number of them, pre¬ 
viously graduated between 90° and 80° and heated to 90°, in air at 
60° or 50°, and to select those which contract according to the time 
fixed on as a standard. The thermometer so applied, Dr. Osborne 
proposes to call a psychometer, or measurer of refrigeration. 
