human
During these labours of the Americans, the enemy continued to annoy them, by throwing shells from the fort.
gpt
Pray, father, what are shells? I have read of them; but I do not know more than that they are a kind of shot.
human
Shells are often called _bombs_, a word which signifies _great noise_; because, when they burst, they make a great noise. They consist of a large shell of cast iron, which is round and hollow. A hole is made through the shell to receive a _fusee_, as it is called; this is a small pipe, or hollow piece of wood, which is filled with some combustible matter. When a bomb is about to be fired, it is filled with powder, after which the fusee is driven into the vent, or hole of the shell.
gpt
How are bombs fired, father?
human
They are thrown from a kind of cannon called a _mortar_. It has its name from its resemblance to a common mortar. The lower part of the mortar is called the _chamber_, which contains the powder. When fired, the powder in the chamber not only sends the bomb, but at the same time, sets fire to the fusee, which continues to burn slowly, as it passes through the air, and the calculation always is, to have the fire from the fusee reach the powder in the shell, _at the moment the latter reaches the ground_. It then bursts, and the scattering fragments of iron often do horrible execution.
gpt
Did you say, father, that mortars Were _short_ guns?
human
Land mortars are quite short; sea mortars, or such as are used on board vessels, are longer and heavier, because they are usually fired at greater distances. A land mortar, which will throw a shell thirteen inches in diameter, weighs thirteen hundred weight; the weight of the shell is about one hundred and seventy-five pounds; it contains between nine and ten pounds of powder; and is fired by means of about the same quantity of powder.
gpt
Pray, father, who invented bombs?
human
Some years after the above affair, Crosby himself related the manner in which the soldiers contrived to escape unhurt. When a shell rose in the air, every one would stop working, and watch its course, to ascertain whether it would fall near him. If it appeared to approach so near, as to endanger any one, he would dodge behind something, till it had burst, or passed by.
gpt
Father, could a soldier dodge a cannon ball?
human
Why, John! I should think you knew enough, not to ask so foolish a question.
gpt
Not so bad a question neither, master Henry; under some circumstances, a cannon ball might he avoided.
human
Not when it is first fired, father.