MINUTES OF PROCEEDINGS OF 
pattern sample as possible. Therefore, as before remarked, all exa¬ 
mination of powder should be mainly a matter of comparison. 
(d.) The quality of freedom from dust or foreign matters can be more 
easily tested. All powders should be absolutely free from dust. The 
only way to make sure of this, is to pour rapidly a quantity of the 
powder from a bowl held two or three feet above the barrel, in a good 
strong light. Even this simple operation requires a little practice to do 
it dexterously, without spilling the powder over the floor of the examining- 
room. If there be any loose dust, it will be readily detected. Powder 
that is glazed with black-lead, should be perfectly free from loose 
particles of the black-lead, and should in no case soil the fingers. The 
presence of other foreign substances in powder, need not be alluded to 
here, as none such could occur in new powder; they are of common 
enough occurrence, however, in returned powder. 
II. Incorporation. —This is tested by “ flashingthat is, by 
burning a small quantity of the powder on a thick plate of glass. 
8 ozs. of the powder are generally flashed. This quantity is put into a 
small copper cylinder, resembling a thimble in shape, and the cylinder 
is then inverted on the flashing plate. This provides for the particles of 
the powder being always arranged in pretty nearly the same way—• 
which is an all-important point in flashing. The decomposition of the 
powder will be more thorough if it be thrown together in a small 
conical heap, them if it be spread out in a thin layer on the plate; 
hence, when comparing two powders, they should be placed on the 
flashing plates as nearly as possible under the same conditions. 
If the powder be thoroughly and effectually incorporated, the small 
charge placed on the plate will “ flash ” or puff-off when touched with 
a hot iron, leaving only some smoke marks on the plate. A badly 
incorporated powder will, on the other hand, leave specks of undecom¬ 
posed saltpetre and sulphur, and will therefore leave a dirty residue. 
But the flashing test, though apparently most simple, is one which, like 
the examination by eye and hand, requires experience to enable an 
observer to form accurate judgments. Though a very badly incorporated 
powder may be detected easily enough, it is by no means easy to judge 
between two powders, both tolerably good, as to which has been most 
thoroughly incorporated. Flashing should therefore be constantly 
practised with all classes of powder; and it is useful to keep some 
samples of specially bad powders (there are few foreign powders which 
will not afford plenty of samples), to flash occasionally for comparison. 
Powder which has once been subjected to damp, will be found to flash 
very badly, no matter how carefully its incorporation may have been 
performed. This arises from a partial solution of the saltpetre having 
taken place, causing a consequent disturbance of incorporation. 
III. Size, shape, and proportion oe the grains. —The shape of 
the grains can, of course, be judged by the eye alone. The principal 
point to observe is whether there be many elongated flat scales amongst 
them. If this be the case, the powder will be rapid in its action, from 
the much greater surface exposed to ignition, and therefore injurious to 
