Not enough to be missed unless they checked their supply more carefully than Casey believed they did; but enough for Casey's purpose nevertheless.
That night, while the moon shone in through the dingy window at the head of his bunk and gave him a little light to work by, Casey sat up in bed and snored softly and with a soothing rhythm while he cut a stick of dynamite in two, capped five inches of fuse for each piece working awkwardly with his one good hand and pinching the caps tight with his teeth, which might have sent him with a bang into Kingdom Come--and very carefully worked the caps into the powder until no more than three inches of fuse protruded from the end of the half stick.

It would have been less dangerous to land with a yell in the middle of the floor and fight the three men with one bare hand, but Casey's courage never turned a hair.
Still snoring mildly, he held up to the moonlight two deadly weapons and surveyed them with much satisfaction.

They would not be so quick, as fiction would have them, but if his aim was accurate in throwing, they would be deadly enough.

Moreover, he could count with a good deal of certainty upon a certain degree of terror which the sight of them in his hand would produce.
When Casey Ryan cooked breakfast next morning, he carried two half-sticks of loaded dynamite under his hand in the sling.

Can you wonder that even he shied at standing over the stove cooking hot cakes and complained that his broken hand pained him a lot and that the heat made it worse?
But a shrewd observer would have noticed on his face the expression of a cat that has been shut in the pantry over night.
Joe volunteered to take another look at the hand and see if blood poison was "setting in"; but Casey said it didn't feel like blood poison.