Naphthalene and the usual malodorous powders are not only very disagreeable, but quite useless.
The doctors were of use to Natasha because they kissed and rubbed her bump, assuring her that it would soon pass if only the coachman went to the chemist's in the Arbat and got a powder and some pills in a pretty box for a ruble and seventy kopeks, and if she took those powders in boiled water at intervals of precisely two hours, neither more nor less.
Gum tragacanth is used in calico-printing as a thickener of colours and mordants; in medicine as a demulcent and vehicle for insoluble powders, and as an excipient in pills; and feltsetting and mending beetles and other insect specimens.
A series of powders is obtained progressively finer according to the time required to settle to the bottom of the vessel.
Rend., 1902, 1 35, P. 73 8) obtained ferrous nitride, Fe3N2, and ferric nitride, FeN, as black powders by heating lithium nitride with ferrous potassium chloride and ferric potassium chloride respectively.