Star.
London, England, 1825-09-27 00:00:00

MAN OF THE COMMITTEE OF SHIP OWNERS.

Royal Mint. sth September, 1125.
Sat—l take the Übe/fly of stating to y 0.4, for the in-
formation of the Comrhittee of Ship Owners, that I have
obtained a Patent for an improved* Manufacture of
Coiner for the Sheathing of Ships.
The investigation which led to my taking out this
Patent, I undertook at the suggestion of the Navy
Board ; who had represented the improvement of
sheathing-copper as an object of the deepest interest to
the British Navy. So much so, that a Council of the
Royal Society was employed to investigate the causes
of the rapid decay of Copper Sheathing.
The principle of my improvement consists in giving
to copper a degree t•f strength decidedly superior to
that po,sessed by ordinary sheathing, and at the same
time rendering this increased strength uniform through
the whole macs.

The importance of this improvement is apparent
from the well kbown fact, that when a vessel is stripped
for re-copptring, the old copper is found very unequally
worn: one portion appears tolerably perfect, another
honey-combed and full of small boles, and a third por-
tion nearly destroyed. From my knowledge of the
mode in which copper is usually manufactured, I con-
clude that this difference in the durability of sheathing
taken from the same skip, arises from the difference of
strength which exists in different portions of the same
charge of copper, when it is manufaCtured according to
the ordinary mode.
Now, my process gives to sheathing copper a strength
de:idedly superior to that possessed by the first portion
specified above; and, therefore, by rendering this
strength uniform, so as to give to ail the sheets of my
patent copper the chance of wearing equably, I calcu-
late, not merely upon its uniform durability, but also
upon its lasting much longer than the least decayed
portions of the abovementioned sheathing.
Having thus explained in what my inVovement
consists, permit me to offer to your notice the follow-

kg citcu":nstances, in justificatiUn of my confidence in
its utility.
The Navy Bond supplied me with some copper
from the bottom of the Batavia, a ship of war, which
was taken from the Dutch in the year 1798._ The stir-

face of this sheathing was smooth and uniform: and
on comparing the edge which had not been in contact
with the sea water, with the centre of the sheet, I found
that after the wear and tear of twenty-five years, it had
lost about 42 per cent. This copper contained a small
portion of tin en its composition.
Another specimen of sheathing was sent me from
the bottom of the Plymouth Yacht,which was coppered
in the year 1796. The wear of this copper was equally
uniform with that of the above; and its loss in the
course of twenty-seven years, I found to be only 8 per
cent. • This specimen contained a portion of zinc.
Ton may thus observe, that the causes (of what nature soever
these causes be) which operate In destroying ordinary copper, have
had comparatively link effect in the two cases Isere specified.
And since it is by alloying copper with small proportions of zinc
and tin, that I have succeeded in obtaining a quality of metal de-
cidedly superior in strength to common copper; and since, by my
mode of treating it, the strength of the manufactured mass is ren.
dered uniform,—l seem justified in concluding that copper, thus
manufactured,l* calculated to resist destruction at least equally with
the specimens mentioned above.
Since obtaining my patent,about thirty vessels have been sheathed
with my copper, md in no case have I had the least complaint
from the owners %Win have done me the favour to use it.

MY Patent Copper is manufactured at the works of Messrs.
Williams. Grenfell, and Co. of Castle 13aynard, Thames.street,
London, and is charged Id. per Ih. more than the market price of
common copper.
Your submitting to the Committee of Ship Owners these particu.
lars will greatly oblige, Sir, your most obedient servant
To G. LyaU, ROBERT servant,
Chairman of the Committee of Skip Owners.

• ‘i.
i

FOUNDAITON STONE OF NSW LONDON
BRIDGE.
The Scottish granite merchants *of Aberdeen, and
those of Hayter, Devonshire, being both alike anxious
to supply the huge undertak ng of London Bridge with
the quantum of stone required, and as the granite of
both is nearly equal in value in every respect, the .chief
struggle between them arose about who should firth!)
the toundation stone, as by obtaining thii point, the
greatest share, if not the whole of the work would its
all probability come to that party.
The Devonshire people brought their stone to Lon-
don a month and more before the imposing ceremony
of laying took place—a beautiful stone, forsooth, of
nearly a square form, ani wrighing about five tons :
they brought it but roughly hewn, having plenty of
time to polish it to a beatitiful smlotliness, never
doubting for an instant but that they would completely
over-reach their Scottish rivals, being quite beforehand
with them, for their stone had nut as yet appeared, nor
no firm report that it would.
Ifowever, two days before the ceremony took place,
the Scottish stone arrived in the Thames ; and D.'nald,
its owner, being apprised of the proceedings of the
Devon quarriers, made use of all his natural caution
and secrecy, he silently put his stone in a barge, in the
dark hour of night, and stole up the River with it to
the coffer-dam, where, obtaining assistance, he soon
swung it (in the dings) above that place where the
Lord Mayor ceremoniously fixed it. Next day, the good people
of Devon brought their's down, glistening from the wharf, highly
finished with the chisel; but bow mortified to the heart were they
en finding a block of Aberdeen granite squared in a masterly
manner, in that simile's intended for their's. The llayter Chief
in anger exclaimed, that " Donald had come too far North for
him;' when the latter replied, after taking a hearty sneesher,
"ten sae, man."