6u6 C A N A L. 
weight of the undermofbeoffir, fo as to make if p>epon- ■ 
derate, in circling rices' where the two. coffers vVovifd 
otherwile be in gferfeCt equilibrium • but, wherfe-the'height 
is-conliderable, theie vVi!] be ajneeeffity for providing fifth 
a.counterpoise, as without it the 'chain r b« becoming more 
weighty every foot it defeersijs, would tend ro’deft oy the 
equilibrium too much, and accelent e the mot ion to ;;n in¬ 
convenient degree. To.guard ag.-.inft" this, let a chain of 
the fame weight, per foot, be appended to the .bottom of 
each coder, of fuch a length as to reach within a few 
yards of the ground, when the • coffer, is at its greateft 
height, as lliewn in fig. 7 ; it will act w:fh its whole weight 
upon the hig-hert coffer, while in this portion ;»but; as that 
gradually defceiids, the chain w-ili reach tlie ground, and, 
being there fup) orted, its v^eight w-11 be dlmi'nifned in 
proportion to its defeent; while the-weight of the chain 
on the oppoliie fide will be augmeived in the fame propor¬ 
tion, fo as to counte'rpoife each other exactly, in evesw fi- 
tuation, until the' up; ermoft- chain is railed from the.. 
grou.nd. AfteYwhich.it will in c-reale in weight no more; 
snd, of courfe, will then give the under coffer that pre¬ 
ponderance which is neceffary for preferving the machine 
heady. Tire under coffer, when it reaches its lowed pe¬ 
tition, will touch the" bottom on its edges, which will then 
fup port it. and keep every thing in the lame politico, till 
it is made lighter for the purpofe of amending. 
“ What conffitirtes one particular excellence of the ap¬ 
paratus here propofed is, that it is not only unlimited as 
to the extent of the rife or depression of which it isfufeep- 
tible ; (for it would not require the" expenditure of one 
droJS more water to lower it one hundred feet than one 
foot j) but it would alio be cafy fo to-augment the num¬ 
ber of pulleys at any one place as to admit'of two, three, 
Jbur, or any greater number of boats being lowered or 
elevated at the fame time; fo that let tire fucc'eftion of 
boats on finch a canal be nearly as rapid as that of carriages 
upon a highway, none of them need be delayed one mo¬ 
ment to .wait an opportunity of palling; a thing that is 
totally impracticable where water-locks are employed ; fur 
the intercourfe, on every canal conflruirted with water- 
locks, is neceffardy limited to a certain degree, beyond 
which it is impofiible to force it. For example: fuppofe 
a hundred boats are following each other, in fuch a rapid 
fuccellion as to be'only one minute behind each other ; by 
the apparatus here propofed, they would all be elevated 
precifeiy as they came ; in the other, let it be fuppofed that 
the lock is fo well conftnuSted as that it takes no more than 
five minutes to dole and open it; that is, ten minutes in 
the whole to each boat, (for the lock, being once filled, 
mufi be again emptied, before it can receive another in the 
fame direction ;) at this rate fix, boats.only could be palled 
in an hour, and of courfe it would take lixteen hours and 
forty minutes to pafs the whole hundred .; and, as the laft 
boat would reach the lock in the fpace of fifty minutes after 
the full, it would be detained fifteen hours and fifty mi¬ 
nutes, before its turn would come to be raifed. This is an 
immenfe detention : but if a fuccellion of boats, at the fame 
rate, were to follow continually, they never could pafs at 
all. In Ihort, in a canal conftruded with water-locks, not 
more than fix boats, on an average, can be palled in an 
hour, fo that beyond that extent all commerce mud be 
flopped ; but on the plan here propofed fixty, or 600, might 
be paffed in an hour if neceffary, fo as to occafion no fort of 
of interruption whatever.” 
In June, 1792, a patent wasgranted to Mr. R. Weldon, 
of Litchfield, tor his invention of an engine or machine, for 
conveying veffels, or rnher weights, from an upper to a 
lower, or lower to an upper, level, on canals, which he de- 
feribes as follows : “ Fig. 11, in the preceding Plate, pre- 
fents a perfpeflive view of the engine, by which the con¬ 
veyance is to be effe&ed, and ot the infide of a lock or 
pound in which it is immerfed ; both which may be con- 
flrudtecl in the form or fhape in the drawing, or otherwile, 
as may heft fuit the different fituations and purpofes re¬ 
quired. The machine, A, coniifls of a trunk, or caillbn, 
iitn bof copper, iron, wood, or other materials,;and of di¬ 
me-.:! ins equal to the reception of veffels, or-other, large 
b i - . a: ,.i weights ; at each end thereof is a door-way, 
v tl.-e vellel. See. is to be floated through, into, or out 
of, t he trunk, and being received therein, and the door then 
fitut v, i-h a given quantity of water to Boat the vefiel, &c. 
and countcrpcife the machine, it may then be eafily raifed 
or lowered at jdeafiire, by means of racks and'pinipns, or 
chains and pulleys, as Ilia 11 be found molt convenient, from 
one level to another, and the veffel, &c. be delivered ac¬ 
cordingly. Breprefents one fide, the bottom, and end, of 
•the lock or pound. C, the door at each end of the- trunk." 
Jj, an aperture at each, end of the lock, one at the upper 
and .the other at the lower level, with a.Hiding gate or bolt, 
mover: by racks or chains - , to receive the end of the trunk, 
to winch it is to be clofely fitted at the time the veffel, 
£:c. Is n ouv'cd or delivered. EE are the uprights, to 
which chains are fixed, and to which racks may alio be 
applied ; and F is the fbaft on which the chains are wound, 
and to which pinions a!fo may be applied, for the pur- 
pofc of-railing or lowering the trunk, which, when brought 
to-the aperture of 'he luck, will be confined there by 
means of levers ; and the'machine is farther regulated by 
means'of a pump, an ah-pipe,- and other apparatus, to be 
applied as occafion may require.” 
bev'era 1 engineer? have a'tempted to-apply the inclined 
plane, for -lie purpofe of forming an eafy communication 
between different levels jn canal navigation, fo as to fu- 
perfede the ufe or neceflity of locks. Mr. Jofliua Green, 
of Ginfgley-in Yorkfhire, received a patent for the fol- 
lowing.plan, dated Jutie 18, 1793: “ Let two principal 
planes be erected, ol good done or brick materials, eight 
or ten times the length of the perpendicular or angle.of 
elevation, the longer the inclined planes the lefs ftrefs will 
lie upon the machinery hereafter deferibed; but upon 
the inclined planes muft be fixed a frame of wood, of half 
or quarter deal balksand, to prevent fridlion, the top 
fide of the wood fiiouid be covered or food with forged or 
cad irom. -A third inclined plane, about two-thirds the 
-length of the other, to be betwixt the other two, for an 
u-fe hereafter deferibed. Secondly, The commercial boats 
I propofe fo be about thirty or thirty-five feet long, feven 
feet wide, and to draw betwixt four and five feet water, 
which I apprehend will contain about twenty tons of bur¬ 
den. One vefiel I propofe to afeend up one inclined plane, 
as the other descends upon carriages hereafter deferibed ; 
then it is fuppofed that one commercial boat draws up the 
other, excepting the friction, which will be eafily over¬ 
come by the machinery. Thirdly, I (hall next deferibe 
the carriages, cr what 1 call cradles, to contain the com¬ 
mercial boats, which I conceive to be the mod difficult 
part of the apparatus, and alfo the mod ingenious. Then 
fuppofe four beams; or half deal balks, joined or framed 
together for the two Tides, of fufficient width for the vef¬ 
fels to Hip in and out when-in the water; on which ac 
count the frame or carriage is to be open at each end, joined 
together at the bottom by three or four crofs timbers, and 
good timber knees at each corner and joint, fuch as bcat- 
buiidprs are accullomedto ufe. And, that the laid boat or 
veffel may ride as ealy as in water, when in the Laid cradle, 
the bottom frame'is to be corded ; it is alfo meant that the 
cording is to be above the timbers that join the bottom part 
of laid cradles. Four or more ftrofig wheels, either of call 
metal, or ftrong- aflt (dank, about four feet diameter, are to 
be added to this cradle-frame ; I think the latter, viz. sfh 
plank, is fafer to truft to, about nine inches thick at the 
centre, and about five inches thick at the rim or periphery, 
the foie of which rim is to be Ihod with forged or call iron. 
Now conies the difficulty of axleing thefe wheels, confid¬ 
ent with ftrength and convenience ; for, if the axletrees 
went over the veffcl, it would be inconvenient to the 
loading, as wool-packs, &c. and, if under the veffel, the 
burden being fo much above the centre of gravity would 
endanger overletting; alfo axles fo long would require 
to be of enormous ftrength ; which difficulties to obviate, 
x ’I propofe 
