194 REPORT—1840. 
ficiently normal for that experiment, and the second experi- 
ment was made, viz.— 
S. 1. Glass tubes drawn out at one extremity were pushed, 
with a rapid rotatory motion, into the auricle and ventricle of 
left side, and the column of blood observed. That in the auricle 
gave no satisfactory result, owing to sanguineous exhaustion 
apparently, and the consequent insufficient distension in dia- 
stole, and slight amount of contraction in systole in the auricle. 
But this much was noted, viz., that a very short column that 
filled the drawn out part, was not drawn in diastole, yet 
neither was it very strikingly lengthened in systole. ‘The ven- 
tricle gave better results, viz.,a column rose rapidly by suc- 
cessive stages, rising some lines at each systole, and continuing 
almost stationary at each succeeding diastole, and at length 
overflowing the tube and pouring over in large drops at each 
systole. 
S. 2. The friction between the heart and pericardium in 
systole and diastole of auricles and ventricles; the tension and 
jerking motion upwards in systole; and softening andsubsidence 
in diastole of the parietes of the ventricles ; the abrupt jerking 
over the orifices in systole, followed by subsidence in diastole ; 
the shortening of the diameters lengthwise, and transversely 
in systole; the immediate succession as by a continued undu- 
latory motion of the ventricular systole to that of the auricles; 
the sensation of an undulation from fundus to apex on the ven- 
tricles; the dimpling in systole of the left auricle (which only 
was observed); and the equality, post mortem cordis, of the two 
ventricles ;—all those former observations were repeated, and 
former results confirmed. 
OBSERVATION XVI. 
S. 1. The second animal's heart when exposed was acting 
with more regularity than the former, and the blunt hook and 
screw were successively tried. In each case material modifi- 
cations of the first sound were repeatedly produced by the in- 
terposition of the instrument between the valves in left interior — 
opening; but the modifications were not constant: and in no 
case was there any attempt made to impede the right interior 
valves. This much however was noted, that on several occa- 
sions the interposition of the instrument was followed by mur- — 
mur in the mitral opening with the systole, and by a more ob- 
tuse character of the first sound, and particularly by a want of 
sharpness of definition at its commencement. But it is to be 
added, that considerable irregularity existed for the greater 
part of the time in the sounds, viz., the first sound seemed 
