You are John Rugby, and you are Jack Rugby.
Shak.
2. An impertinent or silly fellow; a simpleton; a boor; a clown; also,
a servant; a rustic. "Jack fool." Chaucer.
Since every Jack became a gentleman, There 's many a gentle person
made a Jack.
Shak.
3. A popular colloquial name for a sailor; -- called also Jack tar, and
Jack afloat.
4. A mechanical contrivance, an auxiliary machine, or a subordinate
part of a machine, rendering convenient service, and often supplying
the place of a boy or attendant who was commonly called Jack; as: (a) A
device to pull off boots. (b) A sawhorse or sawbuck. (c) A machine or
contrivance for turning a spit; a smoke jack, or kitchen jack. (b)
(Mining) A wooden wedge for separating rocks rent by blasting. (e)
(Knitting Machine) A lever for depressing the sinkers which push the
loops down on the needles. (f) (Warping Machine) A grating to separate
and guide the threads; a heck box. (g) (Spinning) A machine for
twisting the sliver as it leaves the carding machine. (h) A compact,
portable machine for planing metal. (i) A machine for slicking or
pebbling leather. (k) A system of gearing driven by a horse power, for
multiplying speed. (l) A hood or other device placed over a chimney or
vent pipe, to prevent a back draught. (m) In the harpsichord, an
intermediate piece communicating the action of the key to the quill; --
called also hopper. (n) In hunting, the pan or frame holding the fuel
of the torch used to attract game at night; also, the light itself. C.
Hallock.
5. A portable machine variously constructed, for exerting great
pressure, or lifting or moving a heavy body through a small distance.
It consists of a lever, screw, rack and pinion, hydraulic press, or any
simple combination of mechanical powers, working in a compact pedestal
or support and operated by a lever, crank, capstan bar, etc. The name
is often given to a jackscrew, which is a kind of jack.