Initial Set.

This is not generally understood, and yet it bears a very [unclear: important] part in correct testing, since it determines the time that may [unclear: be] occupied in ganging. After adding water and working up a pat, [unclear: it] will be observed how the excess of water lies upon the surface for [unclear: a] page 11 short time in quick-setting and for a longer time in slow-setting cement. Note the time that has elapsed since adding the water until this re-absorption commences. After that time the "initial setting" has commenced, and any disturbance will more or less destroy the constructive value of the cement.