Year: 1886

page_text: I GEORGE POTTER trading as Messrs. George Potter & Company of Bank Corner
Aldershot in the county of Hants Military Musical Instrument Maker do hereby
declare the nature of this invention and in what manner the same is to be
performed, to be particularly described and' ascertained in and by the following
statement:
The object of my invention is so to fit drums of all descriptions such for example
as Cavalry and Orchestral Kettle drums as also Gong Bass and Side drums that
the same can easily and very rapidly be tuned that is to say the heads thereof
which can normally be kept quite loose and slack can almost instantaneously have
the desired tension given thereto.
In the accompanying drawing I shew a plan of the underside of the head of a
drum fitted according to this my invention.
In a suitable position in or on the shell of the drum or as is generally preferable
in or on the strengthening ring or hoop Z fitted in any usual or convenient manner
I mount in suitable bearings the usual steel or other tuning rod A which extends
transversely across the said drum and on the two ends thereof are made or cut or
formed respectively a right handed and a left handed screw thread or worm thread
and on the said tuning rod A are mounted two sleeves B formed respectively with
female or internal worm threads or screw threads corresponding with the aforesaid
threads on the said rod A. Each of these sleeves B carries or supports two
pulleys C through which the usual cords D pass by means of which or through
which the head of the drum can be stretched over the shell F thereof or otherwise
in the ordinary manner and therefore when the rod A is so turned by any suitable
handle E situated outside the said shell F of the drum that the sleeves B with the
pulleys C are caused to approach towards each other and towards the centre of
the drum the desired tension is given to the said head of the drum through and
by the said cords D as is desired and vice versa. Now to carry out my aforesaid
object I make the right handed and the left handed screw threads or worm threads
on the tuning rod A hereinbefore described with an extremely quick or coarse
pitch preferably in such a manner that three threads only that is to say three
complete circumvolutions or turns of the thread round the said rod A only are
made in one inch of the length of the said rod A or thereabouts. The consequence
of this extremely quick or coarse pitch aforesaid obviously is that the drum can
easily and very rapidly be tuned for a very few turns of the bandle of the tuning

page_text: rod will almost instantaneously give any desired tension to the head of the drum
and a very few turns of the said handle of the tuning rod in a reverse direction
will as rapidly relax this tension and allow the said head of the drum to be and
remain slack and loose as is desired.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that
what I claim is
The tuning rods of drums on which are right handed and left handed screw
threads or worm threads with an extremely quick or coarse pitch substantially as
and for the purpose hereinbefore described and declared.