TRANSACTIONS OF THE SECTIONS. 133 
understood ; but careful observation leaves no doubt on the author’s mind that, 
next to apncea or asphyxia, already minutely dwelt upon, this mere coincidence of 
simple syncope is most to be dreaded. 
Observations made at Sea on the Motion of the Vessel with reference to Sea- 
Sickness. By J. W. Osporne. 
The author stated that he had entered upon this investigation during a voyage 
from Melbourne, not with the interest of a physician, whose object it would be to 
cure this distressing malady, but rather for the purpose of establishing the nature 
of the connexion between mechanical movement of the human body, both active 
and passive, with the phenomena of nutrition and waste, functions which mani- 
fested many interesting and remarkable anomalies during an attack of sea-sickness. 
Many observations of a pathological and physiological character had been made 
and recorded ; but it soon became apparent that to obtain results of real value, the 
nature, force, and direction of the movements to which the vessel subjected the 
body, and its several organs, required investigation. To express these mechanical 
influences, three instruments were contrived and used with satisfactory results. 
These instruments were exhibited by the author, and the following is a sketch of 
the description given to the Section. 
The first consists of a spring balance, capable of suspension from any part of the 
ship. By placing a known weight in the pan of this instrument, the deflection in- 
dicated by the index would be constant under ordinary circumstances on shore. At 
sea this was not the case, the pan being there subjected to an unceasing oscillatory 
movement, while the index indicated at one time more, and at another less than 
the figure on the scale corresponding to the weight used. 
The range thus obtained depended chiefly upon the severity of the pitching ; and 
if the divisions of the scale represented fractions of the weight used, the alteration 
in weight of any of the viscera of the human body, with every wave, might be 
arrived at in fractions of their own weight; such alteration being, of course, ap- 
parent only, but acting, nevertheless, upon all supporting ligaments, muscles, &e, 
exactly as if it were real. 
It was well known that the pitching motion of a vessel was very potent to pro- 
duce illness, and in the instrument exhibited, the means were offered for measuring 
and expressing exactly the intensity of this motion; but it was necessary while re- 
cording these readings, to determine what the angular movement the vessel made 
amounted to. To effect this a divided are was made use of, which, while its man- 
ner of suspension permitted of its accommodating itself to one of the angular 
motions of the ship, partook for the time being of the other. Opposite to this are, 
and from the centre of the circle of which it was a part, a plummet or pendulum, 
made of a strip of metal, was freely suspended. The part played by the latter was 
to establish a point from which to read off the number of degrees through which 
either axis of the vessel passed in pitching or rolling. But as the inertia of the 
pendulum caused it to be seriously affected by the impulsive movements to which 
the vessel was subjected in passing through the water, it became necessary to neu= 
tralize these irregularities. This was accomplished by placing in rigid connexion 
with the pendulum a small disk, which travelled through a curved tubular recep- 
tacle containing oil, glycerine, or other viscid fluid, which, while it did not inter- 
fere with the obedience of the plummet to the action of gravity, effectually pre- 
vented the communicated impulses from manifesting themselves in the readings. 
The third instrument was desionad to estimate the force of the impulsive move- 
ment above referred to, and was an arrangement of a somewhat complicated cha- 
racter, in which the oscillations of a pendulum, unaffected by the angular movements 
of the vessel, were read and recorded. These oscillations originate in consequence 
of the inertia or momentum of the ieee itself, freely suspended in a ship vary- 
ing in its rate of motion through the water. 
Several extended series of observations had been made with these instruments 
which were not as yet reduced. nih. 
r 
