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C R A 
St. Dunftan. Its circumference by the outfide of. the 
wall is 733 feet; its length 166, and its width 69. The 
nave or body (which hath a very elegant cieling) is in 
height thirty-fix feet, with fide aides in proportion. The 
height to the top of the battlements on the tower, is 
about feventy-three feet, and to the top of the gilt ftar 
over the vane, which is of curious workmanfhip, nearly 
ninety-four feet. A great part of this church, which is 
fuppofed to be the molt ancient in the weftern divilion 
of Kent, and had a little before coft the parifhioners up¬ 
wards of 800I. to repair, fell down on the 2d of July, 
1725, by one of the chief pillars giving way, whillf the 
bell was tolling to prayers, and by that fall a breach was 
made to the extent of fifty feet, which not only expofed 
the Handing parts of the building to all the inclemencies of 
weather, but left it fo ruinous as to render it unfafe for 
the inhabitants to alfemblc for divine worfhip. The 
damages occafioned by this accident were eftimated at 
2376I. 13s. 9d. and, through contributions by brief, they 
were fo far repaired, that divine fervice was performed 
again in the body of the church, November 7, 1731. On 
Sunday, Auguft 19, 1787, between morning and evening 
fervice, an awful flafii of lightning, attended with tre¬ 
mendous thunder, (truck the uppermoft point of the liar 
over the vane, from whence it defcended by an iron rod, 
fhivered the wood-work in which the vane was fixed, 
and threw feveral of its pieces a long difiance ; it conli- 
derably damaged the (tone-work, pa (Fed to the lead on 
the tower, and defcended through a leaden pipe on the 
fouth fide; from thence it proceeded to the clock-dial, 
tarnifhed fome of the hour-figures, and injured much of 
the wood-work ; it then paifed into the chime-loft, fplin- 
tered the floor in pieces, and vented itfelf at the ealt end 
of the fouth aide, without doing any material damage to 
the body of the church. 
CRANE, f [cjtan, Sax. kraen , Dut.Q A bird with a 
long neck. See Ardea. —Like a crane, or a fwallow, fo 
did I chatter. Ifaiah .—A fiphon ; a crooked pipe for 
drawing liquors out of a cafk. A fouthern confiellation. 
See Grus. An inftrument made with ropes, pullies, 
wheels, and hooks, by which great weights are railed ; 
Then commerce brought into the public walk 
The Dufy merchant, the big warehoufe built, 
Rais’d the ftrong crane. Tho'mfon. 
The crane is one of the mod ufeful inftruments formed 
by a combination of the mechanical powers ; the great 
utility of which, in all ages and countries, has occafioned 
many different confirubtions of it. Perrault, in his notes 
on Vitruvius, deferibes the ancient cranes as being very 
Ample. The modern crane ufually confifts of feveral mem¬ 
bers, the principal of which is a ftrong upright beam or 
arbor, firmly fixed in the ground, and Curtained by eight 
arms, coming from the extremities of four pieces of wood 
laid acrofs, through the middle of which the foot of the 
beam pafies. About the middle of the arbor the arms 
meet, and are mortified into it: its top ends in an iron pi¬ 
vot, on which is borne a tranfverfe piece, advancing out 
fome diftance, like a crane’s neck, vyhence the name. The 
middle and extremities of this are again Curtained by arms 
from the middle of the arbor ; and over it comes a rope, 
or cable, to one end of which the weight is affixed; the 
other is wound about the fpindle or axis of the wheel, 
which, being turned, either by a windlafs, capftan, or 
counter walking-wheel, draws the rope, and fo heaves up 
the weight, juft as a bucket is drawn from a well ; and 
which is afterwards turned to any fide or quarter, by the 
mobility of the tranfverle piece or gib on the pivot. In 
this way two kinds of cranes are conftru&ed: in the firrt, 
or principal one, called the rat-tailed crane, the whole 
machine, with the load, turns upon a ftrong axis ; in the 
fecond, calculated for lighter work, the gibbet alone 
moves on an axis. Several improvements have very lately 
been fuggefted, in the conftruction of this very valuable 
machine, the mort material of which are the following: 
Vol.V. No. 275. 
C R A 
- The reverend E. C. in a paper publifhed in the Re¬ 
pertory of Arts, No. 11, 1795, obferves, “ That a crane 
adting upon a fimple and certain principle, by which the 
man walking in the wheel can lower goods with fiafety 
and expedition, has been long confidered as a great defi- 
deratum in mechanics. Repeated premiums have been 
offered by the fiociety for the encouragement of arts, to 
induce ingenious men to attempt the invention of fuch a 
machine ; and various have been the contrivances for 
accomplifliing fo defirable a purpofe; yet mort of them 
have been much too complicated in their conftrudtion, 
and in their operation too uncertain. It feems in this 
bufinefs, as in half the concerns in life, that the object 
in purfuit has been overlooked by the purifiers extend¬ 
ing their views too far. The whole ought to be accom- 
plilhed by a very fimple and obvious contrivance; and this 
may be done merely by introducing the adtion of a worm. 
Whenever a worm is introduced into a machine, all re¬ 
trograde motion is (topped, unlefs the worm receives its 
re-adtion from the firlt moving power; for, powerfully 
as a worm adts upon awheel, a wheel has no power upon 
a worm, whatever force may be applied to it. Suppole 
then the firrt motion in a crane were given by a worm, 
upon the axis of the wheel in which the man walks; 
the man woiMd have perfedt command of the machine, 
to raife or lower the goods at pleafure, without the re- 
moteft poflibility of being overpowered by the defeend- 
ing weight. 
“ Two objedtions, I am aware, maybe brought againft 
the method propofed ; the one, from the greater fridtion 
there is fuppofed fo be between a worm and wheel, than 
between two wheels ; the other, from the (lownefs of the 
motion. This laft objedtion I conlider as nothing; all 
the neceffiiry fpeed being to be gained by the firrt pair of 
wheels, and the diameter of the barrel of the windlals. 
The other objedtion does not (trike me as of much force : 
I grant the fridtion is confiderable ; yet, from its not 
being by intervals, as the friction between the teeth of 
wheels is, and on that account being a diftindt objedt of 
fight, I apprehend we eftimate it, in the companion, as 
more confiderable than what it really is. But as the - 
fridtion, whatever it .may be, between the teeth of two 
wheels, muft be, while it lafts, greater than between a 
worm and wheel for the fame fpace of time, it feems to 
me no unreafonable. fuppolition that the aggregate of 
fridtion will, in the two cafes, nearly balance each other; 
efpecially’ if it be taken into the account, that, to obtain 
the power of one worm and wheel, there will be in molt 
cafes required two pair of wheels, and two additional 
axifes, all which will add to the fridtion. ButJ granting 
the balance of fridtion to be againft the adtion of the 
worm, the power to overcome it is greater in proportion 
than to overcome the fridtion. of two.wheels. In fpeak- 
ing of the fridtion between the teeth of wheels, I con'll - 
der wheel-work as it is ufually conftructed. Wheels, the 
teeth of which are formed upon the true epicycloidal 
principle, I am well apprifed, adt with no perceptible 
fridtion ; but fuch wheels are not yet perfedted, 
“ Were I to conftrubt a crane upon the principle fug¬ 
gefted above, I would have the axis of the wheel in 
which the man walks, and the axis of the worm, in fe- 
parate parts, and occafionally united by a coupling-box. 
When goods were to be railed, the two axiles (hould be 
connedted ; when lowered, they might be dii'unitcd, and 
the worm turned by a winch, which would be done much 
more expeditioufly that way than by the wheel. For the 
reafons before luggefted, the defeent of the weight could 
be accelerated, or (topped, at pleafure, at the diferetion 
of the perfon turning tJie winch. This contrivance might 
be conveniently applied to a crane already eredted upon 
the common principle : let there be a-wheel put upon 
any axis in the machine as it now (lands; upon this let 
there lie a worm, that can be thrown in or out of gear 
at pleafure ; and let the lever, by which it is done,'" - lie 
within reach of the man’s hand in.the walking-wheel. 
4 N ° T he 
