"Comforting himself with this reflection, Mr. Lowten extracted
the plug from the door-key; having opened the door, replugged
and repocketed his Bramah, and picked up the letters which the
postman had dropped through the box, he ushered Mr. Pickwick
into the office. Here, in the twinkling of an eye, he divested
himself of his coat, put on a threadbare garment, which he took
out of a desk, hung up his hat, pulled forth a few sheets of[]b]cartridge and blotting-paper in alternate layers, and, sticking a
pen behind his ear, rubbed his hands with an air of great satisfaction."

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Source: Webster's Revised Unabridged Dictionary (1913)

Cartridge \Car"tridge\ (k[aum]r"tr[i^]j), n. [Formerly cartrage,
corrupted fr. F. cartouche. See Cartouch.] (Mil.)
A complete charge for a firearm, contained in, or held
together by, a case, capsule, or shell of metal, pasteboard,
or other material.

Ball cartridge, a cartridge containing a projectile.

Blank cartridge, a cartridge without a projectile.

Center-fire cartridge, a cartridge in which the fulminate
occupies an axial position usually in the center of the
base of the capsule, instead of being contained in its
rim. In the Prussian needle gun the fulminate is applied
to the middle of the base of the bullet.

Rim-fire cartridge, a cartridge in which the fulminate is
contained in a rim surrounding its base.

Cartridge bag, a bag of woolen cloth, to hold a charge for
a cannon.

Cartridge belt, a belt having pockets for cartridges.

Cartridge box, a case, usually of leather, attached to a
belt or strap, for holding cartridges.

Cartridge paper.
(a) A thick stout paper for inclosing cartridges.
(b) A rough tinted paper used for covering walls, and also
for making drawings upon.

i remeber reading once that american frontiers men made a habit of pouring a shot of 'powder' into a slip of paper, so that they could bite/tear the package open, pour a 'measured load' of black powder, drop in a 'bullet'(shot) and then fire.. (being able to reload fast was important when dealing with a wounded deer, or an attacking bear!)

these pre-measured doses of powder were quicker than the then common way of pouring the powder from a horn.. and quickly became the standard way of 'loading' a gun. from there, evolved the cartridge-- powder and shot all in one neat package, to drop down the barrel of gun/rifle, so you could reload even faster.--(a british innovation, i think)

some restoration villiages nowdays make 'cartridges' out of aluminum foil, (no bullet/shot, just powder)--its easier to get the size right-- the 'cartidge' goes down the barrel, and the gun goes 'boom' --homemade blanks for antiques style guns.