ggle to know the truths
of disease, which is little understood beyond the ranks of the most
scholarly of my profession. The first step was due to Galileo. In 1585
he used his pendulum to record the pulse, in a fashion at which we smile
to-day, and yet what he tried to do was the birth of precision in
medicine. Keeping a finger on the pulse, he set a pendulum in motion. If
it went faster than the pulse, he put the weight a little lower, or as I
may state it to make it clearer, he lengthened the pendulum. At last
when it moved so as to beat equal time with the pulse, he measured the
length of the swinging bar, and set down the pulse as, say ten inches;
next day it might be set at six, and so a record was made. He was soon
lost to medicine, but in 1625, Santorini, known to science as
Sanctorius, published a curious book, called "Commentaries on Avicenna,"
in which he figured a variety of similar instruments, called
"pulsilograms." We owe to him some of the first accurate studies of
diet, and also the discovery of the insensible perspiration, but his
pulsilogram was soon forgotten.

I think that Harvey but once or twice mentions the number of the pulse
even in his physiological books. In the case descriptions of his time
and of Sydenham's it is rare to find it noted, and this is true as a
rule all through the next century. The exceptions are interesting. In
Whytte's works, _circa_ 1745, he not rarely mentions the pulse number in
connection with his primary delineation of a case, but after that does
not often speak of its subsequent changes in number. The force and other
characters of the pulse receive, however, immense attention, and are on
the whole more valuable aids than mere numeration; but that cannot
nowadays be left out of our calculations, yet as early as the reign of
Anne, about 1710, an English physician, Sir John Floyer, wrote an able
and now half-forgotten book, quaintly called the "Pulse Watch." I am
pretty sure that he was the first to put a minute-hand on a watch to
enable him to time the pulse-beat, but nowhere in any English collection
have I been able to find one of his watches. Thus aided, he was the
first to count the minute's pulse, which is now a sort of recognized and
accepted matter as standard of comparison, so that we say merely, the
pulse was 60 or 90, as may chance, and do not even speak of the minute.
It is as true as strange that this convenient method was practically
lost to habitual use in me