212 
orstability to the vessel, butit destroys the 
good effects of the unequal suspension of 
the yard, and turns it into a positive dis- 
advantage when close-hauled in that way, 
for the reasons above stated. Whether 
the Chinese or European, or what other 
proportion for slinging a lug-sail yard, 
gives the true fulerum, should be tried 
by experiment; but no nation seems 
to be aware of the necessity or practi- 
cability of making the point of suspen- 
sion, technically called the sling and 
truss, or halyard and parl, moveable on 
the yard, and for making the lifts adapt 
their tension to that movement, which 
with the traverse of the sheets of top- 
sails and top-gallant-sails, and the re- 
moval of impediments from the stand- 
ing rigging, to allow the yards to be 
braced up to 20° instead of 35° to 40° 
obliquity as at present, constitute the 
sine gua non for combining, in one sail, 
the good properties of the square-sail 
and the lug-sail, free from their present 
defects and inconveniences. 
The measure of the superiority of the 
lug-sail over the square-sail, when close- 
hauled, will be found theoretically in 
the difference between the angles they 
severally make with the keel of the ves- 
sel, as the lug-sail carries its tack amid- 
ship, or nearly so, and the square-sail 
carries its tack on the weather gunnel or 
nearly in a line with it; but practically, 
the measure of that superiority consists 
in the difference between the angles cf 
the courses made good to windward by 
a lug-sail, and a square-sail rigged ves- 
sel, which is commontly a point anda 
half of the mariners’ compass, that is 
16° 522” in favour of the lug-sail. How 
far leé-way may diminish or increase 
that angular difference made good to 
windward, depends upon circumstances 
of weather, and the sailing properties of 
particular ships and vessels, and upen 
the fact that leeward tides and currents 
sweep away square-rigged ships more 
than fore and aft-sail vessels, because 
they strike the former more on their 
broadsides in proportion to that angular 
difference, but in general the difference 
of leeway is againsta square-rigged ship. 
The importance and possibility of ad- 
ding that anguiar difference, made goed 
to windward, to the present course of 
a square-rigged ship when close-hauled, 
appears from this fact, that although 
she will lay or look up to five points 
anda half, she loses headway if kept 
nearer to the wind than a six-point 
course, to which if we gd the lee-way 
and stern-way in stays of a square-rig- 
Miller on the Sailing Properties of Square- Rigged Ships. 
(Oct. I, 
ged ship, which are seldom less than 
one point even in smooth still water ; 
it will be evident that a square-rigged 
ship makes good to windward but one 
point out of eight contained in a quar- 
ter of the compass, that is, an angle of 
but 1]4° out of a right angle, or 90° 
in the most favourable circumstances, 
which angle of 114° is often insufficient 
to countervail occasional disadvantages, 
such as the send or drift of a heavy 
head sea, the veering of winds a-head, 
yaws from bad steerage, and leeward 
tides or currents, as in such circum- 
stances she cannot make good a better 
course than she would sail with the 
wind on her beam. Hence it is impos- 
sible for a common ship to make a pas- 
sage against steady adverse winds, like 
trade-winds and monsoons, or even to 
clear land or ice when embayed in bad 
weather, unless she happens to be fa- 
voured by windwardly tides or currents, 
or their eddies, or by occasional slants 
or veerings of wind, and therefore a 
common ship is inadequate to the safety 
of life and property, and to the neces- 
sary operations of commerce and of war. 
But the proposed combination of the 
good qualities of the lug-sail and square- 
sail in one sail; and the application of 
the principle of that improtement to 
all the square-sails of a ship, by a lateral 
and simultaneous movement, would con- 
stitute a ship-lugger superior in wind- 
wardly power, by 83°45” including both 
tacks, and in velocity both by and large, 
or before the wind, to any common ship, 
and that could go to sea and make a 
passage, when a common ship must lie 
in port, or would be cast away. 
The proposed ship-lugger could dis- 
pense with all the sails that are above 
excluded, because two-thirds of a lug- 
sail when close-hauled, being to leeward 
of the mast, the lug square-sails for that 
reason and because of thew sharper 
trim, would occupy those positions to 
which stay-sails, try-sails, and gafftop- 
sails are now applied for the purpose 
of intercepting certain streams of wind 
that escape between the-common square 
sails of different masts, and as the lug- 
square-sails would be more powerful 
and windwardly than any of the sails so 
dispensed with, because a stay-sail pro- 
perly so called, being triangular, is but 
half a regular sail, anda gaff or try-sail 
is but two-thirds of a regular sail on 
the principle here stated. The best of 
the stay-sails new in use, viz. the main 
top-mast stay-sail, has little effect ex- 
cept when going a point free, and 
though 
