The Liverpool Standard and General Commercial Advertiser.
Liverpool, Merseyside, England, 1843-02-07 00:00:00

developetnent of chance

ks a shipowner, and anxious to aid in furthering the im-

. •
provement and efficiency of our merchant ships, our author

submits hls scale for roasting and sparring,

in the hope (as

ie modestly remarks

of enlisting others in the cause, in-

viting examination and suggestions, and thus eventually ar-

riving at something like the same uniformity and symmetry
for which our ships of war are so justly celebrated and ad-

mired." As bearing on the general question of improve-

went, he ascribes the inefficiency of some portion of our mer-
chant ships, commanders, and officers, to the changed cir-

cumstances of the times. Formerly our shipping (with the ex-
cention of East Indiamen) was more fitted for the transport,
Baltic, and coasting trades, " and vessels and commanders
suited for such trades, have, from the increased demand for
tonnage, since the abolition of the Company's ships, and the

opening of the China trade, been brought into a service
foreign to their capability." The remark, he conceives,

equally applies to our colonial-built ships, which have been

brought into requisition by the forced demand for tonnage,
during the joint-stock bank mania and open credit system ;
but the evil, be considers, is rapidly curing itself, without
the mischievous interference of the legislature (proposed by
Csptain Fitzroy); and he looks for its final extinction to the
" great change going on the mercantile world" owing to the
diffusion of the existing knowledge amongst the mass of man-
kind, which was formerly out of the reach of the humbler
classes. " Now," he remarks, " competition for profit and
distinction is springing up on all sides ; and when we find
old establishments are adapting themselves to the spirit of
the age, it is only fair to infer that our ship-builders and
ship-owners will be keenly alive to their own interests, and

make the prospective improvement of our merchant ships,
and the condition of the commanders and officers, their grand

Our author introduces the subject of roasting and sparring,
by stating that " a very erroneous impression exists in the
minds of many mere practical men, that, in proportion to
the tautness of the masts, and the squareness of the yards
and sails, so would the sailing of the ship be increased or di-
The falacy of this theory has been practically de-
monstrated in many instances on record, of ships, very
squarely rigged, having sailed muck faster when reduced to
jury masts and spars." This, he adds, is scientifically ac-
counted for ; and he quotes a passage in illustration from Dr.
Arnott's interesting work on the " Elements of Physics," in
which he shows that the same force is required to give or
take away, or to bend a motion, in a fluid, as in an equal
quantity of solid matter, and that it is a mistake to suppose
that if a body moving through a fluid at a given rate meets a
given resistance, it just meets double resistance when moving
twice as fast. The resistance is, in fact, four times greater
with a double rate. " A boat which moves one inch an hour
displaces a certain quantity of water, and with a certain velo-
t, of course, displaces twice as
id requires to be moved

minished

if it move twice as fast,

many particles in the some time

force on that account ; but it also displaces
every particle with a double velocity, and receives another
doubling of the power on this account ; the power being thus
doubled on two accounts, becomes a power of four." In the
same manner, wi resistance, speed of three, a force of nine is required
to overcome the and so on with other proportions,

with twice tr

as thus—

8 9 10

25 36 49 64

SI 100