The morning call. [volume] (San Francisco [Calif.]) 1878-1895, 1895-02-17

NJ Some interesting rec
ords have recently been made by c. G.
Stewart of the daily activity of certain
small animals and of the changes effected
by various influences. Thus far the ami
mails experimental on have been rats,
mice and squirrels. They are kept in cir
cular, easily rotated cages, so arranged
that any motion of the animal rotates the
cage and by means of a tambour or levers
this motion of the cage is recorded
upon kymograph paper kept moving night
and day. An electromagnetic circuit with
a clock marks hours and minutes. We
thus have the manner in which an animal
divides his time between rest and activity,
recorded by himself. Rats and mice divide
their days into about twelve hours rest
and twelve hours intermittent work dur
ing the night Those of us who are wake
Jul will, however, be inclined to believe that
these creatures ramble and nibble all
night. During the work period short
intervals of activity, rarely exceeding an
hour, are interrupted by almost equal
periods of rest The squirrel in winter
works almost continuously for from
twenty minutes to two hours early in the
morning, with sometimes short interval
of activity late in the evening, and rests
nearly twenty-five hours in the day.
Food has marked influence upon diurnal
activity. In general the richer the diet in
proteid, the greater the activity Fat has
the opposite effect, reducing the activity
of mice from to hours actual work to a
few minutes day. To test the influence
of alcohol on spontaneous activity, rats
kept on dry corn were given instead of
water alcohol OF 5 per cent to go per cent.
7 I
effect of alcohol could be demonstrated.
All normal animals experimental on
tended to work more minutes per dav
when barometric pressure was high, and
this must be taken into careful account in
estimating the effect of any condition upon
daily activity.
STORED ENERGY IN A WATCH. The pocket
watch of to-day is one of the most accu-
rate of all instruments of precision Briefly
defined mechanically it is a spring motor
of most delicate construction of parts con-
troled by an automatic regulating device
that is marvel of precision. 1t is de-
signed to measure accurately and record
the hours, minutes and seconds of the
mean solar day. A watch keeping time to
minute week varies from true precision
only 1-100 of 1 per cent. The act of
Winding, SO Caleu, is Cnat OF storing UP
energy in spring. BY this act of wind
ing the hand in an interval of about fifteen
seconds stores up energy enough to keep
the motor in motion and to supply the
maximum of power required for period
of twenty-four hours and with reserve in
the modern watch of about sixteen hours
or, in other words, a modern watch will
run for period of forty hours from the
energy that is stored in it by the hand in
fifteen seconds of winding-96O0 times the
length of time employed in the winding.
The storage of power in such a stan
dard is effected by means of a rib
bon of steel of a width and thickness
proportional to the size of the watch and
which is contained in the first wheel, called
in technical parlance the barrel, which is
in the form OF a cup. The size of this cup
is governed by the size of the watch, being
nearly one-half the size or diameter of the
frames of the watch. This spring is from
Is to % inches long. 1t is coiled up in the
barrel with its outer end secured by means
of a pierced hole, fitting over suitable
hook or stud, projecting inwardly from the
barrel. Its inner end is secured to sim
liar hook to the hub of wheel, called the
first or main wheel. BY the act of winding
this spring is wrapped around this hub
and the wheel is caused to revolve. The