Excerpt from the War Department Field manual for M1911, dated April 1, 1912...
A loaded magazine is placed in the handle and the slide drawn
fully back and released, thus bringing the first cartridge into the
chamber (if the slide is open, push down the slide stop to let the
slide go forward). The hammer is thus cocked and the
pistol is ready for firing.
If it is desired to make the pistol ready for instant use and for
firing with the least possible delay the maximum number of shots,
draw back the slide, insert a cartridge by hand into the cham-
ber of the barrel, allow the slide to close, then lock the slide
and the cocked hammer by pressing the safety lock
upward, and insert a loaded magazine. The slide and hammer
being thus positively locked, the pistol may be carried safely at
full cock, and it is only necessary to press down the safety lock
(which is located within easy reach of the thumb) when raising the
pistol to the firing position.
The grip safety is provided with an extending horn, which
not only serves as a guard to prevent the hand of the shooter from
slipping upward and being struck or injured by the hammer,
but also aids in accurate shooting by keeping the hand in the same
position for each shot ; and, furthermore, permits the lowering of the
cocked hammer with one hand by automatically pressing in the
grip safety when the hammer is drawn slightly beyond the
cocked position. In order to release the hammer, the grip
safety must be pressed in before the trigger is pulled.
SAFETY DEVICES.
It is impossible for the firing pin to discharge or even touch
the primer, except on receiving the full blow of the hammer.
The pistol is provided with two automatic safety devices :
The (automatic) disconnector which positively prevents
the release of the hammer unless the slide and barrel
are in the forward position and safely interlocked; this device also
controls the firing and prevents more than one shot from following
each pull of the trigger.
The (automatic) grip safety at all times locks the trigger
unless the handle is firmly grasped and the grip safety
pressed in.
The pistol is in addition provided with a safety lock by which
the closed slide and the cocked hammer can be at will posi-
tively locked in position.