Farrow's military encyclopedia : a dictionary of military knowledge . n in the same positionin the square and be the same distance from the in-terior surface of the gun, throughout an entire revo-lution, showing that the axis of the gun and lathecoincide. With the hollow-cast gun it is necessarythat it should be centered from the bore, as it some-times happens that its axis does not coincide withthe axis of the casting, which is one reason for cast-ing them above the true size, to admit of beingfinished by the interior, or so that the axis of thecast bore shall coincide with that of the gun wh
Farrow's military encyclopedia : a dictionary of military knowledge . n in the same positionin the square and be the same distance from the in-terior surface of the gun, throughout an entire revo-lution, showing that the axis of the gun and lathecoincide. With the hollow-cast gun it is necessarythat it should be centered from the bore, as it some-times happens that its axis does not coincide withthe axis of the casting, which is one reason for cast-ing them above the true size, to admit of beingfinished by the interior, or so that the axis of thecast bore shall coincide with that of the gun whenturned. The gun being centered, the turning com-mences at the muzzle; this is done by placing a toolin the rest, which is brought in contact with thesurface at tlie desirad point, the metal being turnedoff as tlie gun revolves. The re»t. or support whichholds the tool, is arranged to move in two directions,one towards the gun, or at right angles to the axisof the lathe, by which means the depth of cut is regu-lated, and the other in line parallel with the ,. Iltjuliii dimensions wliile in this lathe, as the chase andinunded pari of the cascalicl-knob form the bearingsfor the boring-lathe. The cut at th, muzzle, or placewhere tlie ninkiiig-head is to be broken off. is alsomade in this lathe. Tli.; bearing in which this muz-zle-ring revolves is a heavy casting, the bottom ofwhich fits into grooves in the rack, and can be movedto or from the chuck, being adajjtable to long orshort gtins. To maki^ the ailjustnient in the lathe,the sun is lowered into place, the scpiare knob inrear of the cascabel fitting into tlie chuck, while the that is from muzzle to breech. The last movementis elTeeted by means of a//, the motion being givenby a fork attached to cine of the trunnions, ami atevery revolution of the gun the rest is made to ad-vance. The first cut is usually an inch deep, com-mencing at the muzzle where the sinking-head is tobe cut off and extending 30 inches towards thetr
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Keywords: ., bookcentury1800, bookdecade188, booksubjectmilitaryartandscience
