CERTAIN IMPROVEMENTS IN OR ON INSTRUMENTS AND APPARATUS FOR ASCERTAINING THE STRENGTH OF SPIRITOUS LIQUORS, AND ALSO THE SPECIFIC GRAVITY OF FLUIDS AND METALS
Year: 1818

page_text: TO ALL TO WHOM THESE PRESENTS SHALL COME, we, JOHN
ASHTON, of Great Tower Street, in the City of London, Wine and Brandy
Merchant, and THOMAS GILL, of Greek Street, Soho, in the County of Mid-
dlesex, Hydrometer Manufacturer, send greeting.
WHEREAS His most Excellent Majesty King George the Third did, by
His Letters Patent under the Great Seal of the United Kingdom of Great
Britain and Ireland, bearing date at Westminster, the Fourteenth day of
March, in the fifty-eighth year of His reign, give and grant unto us, the said
John Ashton and Thomas Gill, our exors, adññors, and assigns, His especial
licence, full power, sole privilege and authority, that we, the said John Ashton
and Thomas Gill, our exors, admors, and assigns, should and lawfully might,
during the term of years therein expressed, make, use, exercise, and
vend, within England, Wales, and the Town of Berwick-upon-Tweed, our
Invention of "CERTAIN IMPROVEMENTS IN OR ON INSTRUMENTS AND APPARATUS
FOR ASCERTAINING THE STRENGTH OF SPIRITOUS LIQUORS, AND ALSO THE SPECIFIC
GRAVITY OF FLUIDS AND METALS;" in which said Letters Patent there is con-
tained a proviso, that if we, the said John Ashton and Thomas Gill, or one of
us, shall not particularly describe and ascertain the nature of our said Invention,
and in what manner the same is to be performed, by instrument in writing
under our hands and seals, or under the hand and seal of one of us, and cause
the same to be inrolled in His Majesty's High Court of Chancery within six
calendar months next and immediately after the date of these our Letters
Patent, that then these our Letters Patent, and all liberties and advantages
whatsoever hereby granted, shall utterly cease, determine, and become void, as

page_text: in and by the same, relation being thereunto nad, may more fully and at large
appear.
NOW KNOW YE, that in compliance with the said proviso, I, the said
John Ashton, do hereby declare that the nature of my said Invention, and
the manner in which the same is to be performed, are particularly described
and ascertained in and by the Drawings hereunto annexed, and the following
description thereof (that is to say):-
The Figures of the Drawings hereunto annexed represent two different
descriptions of a thermometer, and likewise of an hydrometer for charging the
strength of spirits on importation, and for the various branches of the spirit
trade, which machines are both constructed according to the improvements
which we have invented. The one of these hydrometers is made with two
sides, or a flat stem, comprising a range of strength from 25 p' cent. under
to fifty-five over proof. The other with four sides, taking the range from
water to 65 per cent. over proof; the indications on the stem, in both, being
represented in per-centages by a series of graduated divisions proportioned to
the contraction and expansion of spirits. The thermometer applying to these
hydrometers corresponds with the stem of the hydrometer and points out the
application of the temperature weights, so as to preserve a constant uniformity
through all its ranges (see Fig. 1 in the annexed Drawing); the two-sided
hydrometer (principally applicable to the charging of spirits on importation,
and described by Fig. 2 in the annexed Drawing, is used with only one
charging weight, marked P, R, the remaining eighteen engraved, from A to S,
being meer regulators for temperature, are in effect but as one more. Tho
charging weight is applied when the spirit comes within the denomination of
25 p cent. under proof, and 20 per cent. above proof. Beyond the later
point the instrument acts without any charging or other weight than that for
the temperature. Immerse the thermometer in the spirit, and supposing the
mercury to stand at the letter a, and not higher than half a division above
it, the weight marked A is to be applied to the lower rest of the bottom stem
of the hydrometer, as the regulating weight for temperature; when the
mercury rises to the half division above A, apply the weight engraved B, until
the mercury rises to the half division above B, then apply the weight C, and
so of all the rest. Having ascertained the temperature of the spririt, and
applied the regulating weight for that purpose, then affix the charging weight
engraved P, R, on the upper rest of the same stem, and immerse the hydro-
meter nearly to the top; when it has become stationary, whatever part of the
stem is cut by the fluid denotes instantaneously, and by its own simple
operation, the strength in per-centage of any spirit from 25 per cent. under

page_text: proof to 20 over, which comprises one side of the hydrometer. If above that
strength, then take off the weight engraved P, R, and the result is given by
reference to the reverse side, comprehending from from 20 pr cent. to 55 over
proof, without the aid of a charging weight, or any other than that for the
regulation of temperature. The four-sided or square-stemmed bydrometer,
designed principally for the use of the malt distillers, rectifiers, and general
dealers in spirits, and described, Fig. 3, in the annexed Drawing, comprizes a
range of strength from water to 65 per cent. above proof, and has three
charging weights, engraved P, R, No. 1, No. 2, and W, No. 3. Having
ascertained the temperature and applied the regulating weight, as before
directed, allix the charging one marked P, R, No. 1, on the upper rest of the
lower stem, and immerse the hydrometer in the spirit, by which will be shewn
a range in strength from 25 per cent. under proof to 15 over;
if stronger,
substitute the one engraved No. 2, having reference to that side of the hydro-
5 meter marked 2, comprising a range from 15 to 45 per cent. over proof; if
above that strength, remove the last charging weight and use the instrument
with only that for regulating the temperature, refering to that side of the
hydrometer marked 3, on which will be found the strength of any spirit from
45 to 65 per cent. over proof. For the remainder of the strengths compre-
hended from water to 25 per cent. under proof, use the charging weight
ungraved W, No. 3, refering to that side of the hydrometer engraved W. At
the bottom, representing the water point, where it may be necessary to attain
greater precision, the thermometer is divided into halves and fourths, and with
an intermediate set of temperature weights, in addition to those from A to S,
viz, numbered from No. 1 to 17, which describe the half divisions (see
Figs. No. 4 and 5) in the annexed Drawing. To addapt the thermometer
to tropical climates the indications on its scale must be continued fron S to Z,
and the corresponding temperature weights be added. The hydrometer for
ascertaining the specific gravity of fluids and solids (see Fig. 6 in the annexed
Drawing, differs but little in principle from that for spirits, and may be made
descretionally with any number of divisions on its upper stem, answering to
units of specific gravity. The scale of the thermometer (when one is requisite
to be used) is graduated or divided so as to act in unison with the stem of the
hydrometer; temperature weights may be either used or not with this
instrument; if used, they must be applied as before directed. In the spirit
hydrometer, the ball or bulb of the hydrometer may be made of any form,
substance, or material, but a metallic substance is preferrable. In ascertaining
the specific gravity of metals, such as coins, it becomes necessary to have a
double set of weights, the one for weighing the coin or metal in air, and the

page_text: other in water, which are distinguished by the letters A and W, marking the
relative difference for each element. This hydrometer is provided with a
bucket or pan (marked a) fixed on the lower stem, the upper stem being
furnished with a cup or cap (marked b); to ascertain the specific gravity o
the coin or metal, place the piece under examination (suppose a sovereign) in
the cup on the upper stem of the hydrometer, to shew its weight in air, and
the weight corresponding with the valve of the coin (and marked sovereign A)
in the bucket on the lower stem, and if the coin is the proper weight it will
sink the hydrometer in distilled water to the division on its upper stem,
corresponding with the temperature, as indicated by the immersion of the
thermometer. Then reverse the experiment, by placing the coin in the bucket
or pan on the lower stem, and the other weight (marked sovereign W) in the
cup on the upper stem, and if the coin is of its standard it will sink the
hydrometer in distilled water to the same division as on its trial in air. Should
the coin on being weighed in water not sink the instrument to the same
division on its stem as when weighed in air, but to some lower one, the
deficiency of its specific gravity will be clearly demonstrated. The thermometer
may generally be dispensed with in weighing coins, the principle point to be
regarded in all experements being an uniformity of weight in air and water,
and it will be sufficient if the indication on the stem of the hydrometer comes
near the temperature standard marked S in those experiments where the
thermometer is not used.
In witness whereof, I, the said John Ashton, have hereunto set my hand
and seal, this Fourteenth day of September, in the year of our Lord
One thousand eight hundred and eighteen.