The value of dusting powders is determined partly by their capacity for absorbing or retaining excessive fluid, for
example, from the skin, from open wounds, from the intestine in dysentery, etc.
These uses suggested the desirability of ascertaining the relative water absorbing capacity of these dusting powders. This was done by shaking 3 gm. of the powders with an excess of water, throwing on a filter and permitting to drain quite thoroughly, and then weighing the moist powders. All experiments were made at the same time, so as to make the results comparable. They are shown in the accompanying table.
The commonly used dusting powders do not differ very materially in their capacity for holding water. However, starch, kaolin and fullers' earth are more effective than chalk or talcum.