It is of less importance in this class of carriages than in any other, as they are seldom removed from their situations: their weight adds but little to the labor of running them up.
36. Mention the different stationary carriages.
The carriage from which a mortar is fired, called its bed; the barbette-carriage; the columbiad-carriage; the casemate-carriage; and that for the 24-pdr. iron howitzer, called the flank-casemate carriage.
37. How many kinds of siege mortar beds have we?
Four; the 8-in., 10-in., the stone, the coehorn.
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38. Which of these are alike?
The first three, differing only in dimensions. They are made of cast-iron, which has very little elasticity.
39. Describe these beds.
They consist of two cheeks, joined by two transoms, all cast together in the same piece. The manœuvring bolts, placed on each side, one near each end of the cheeks, are made of wrought iron, and set in the mould when the bed is cast.