MECHANIC S. 
the prefence of ten or twelve competent perfons, been 
brought to the moft decifive proof; and it comes out, 
that it is as indifferent to draught, as it is material to dan¬ 
ger or fafety, whether a ton be placed on the roof of a 
coach, or a ton on the floor of the patent luggage-box, 
about fifteen or fixteen inches from the ground. 
It has been afked, “ What would this coach do in 
fnow ?” The queftion has been thus anfwered by the re- 
fultof aftual work; for the patent coach, after being de¬ 
tained on the road with f'everal other coaches byafudden 
fall of fnow, when at laft they ftarted together, came in fix 
or feven hours before any of them. They were bound in 
prudence to go cautiouily along the ground, whofe un- 
evennefs was invifible; while the patent coach dallied 
along it with all the confidence and fafety of a polt-chaife. 
Thus much of coaches. The following improvements 
relate chiefly to carts ; and of thefe the firft rank is due 
to the alexippos, or horfe-helper, a. curious invention, for 
which the thanks of the Society for the Encouragement of 
Arts, &c. were voted to Mr. John Snart, optician, of 
Tooley-ftreet, London. It is defigned to be fixed to the 
under fide of a cart, for the relief of the horfe when thrown 
down and entangled in the thills. We earneftly wifh, for 
the fake of humanity, to alleviate the cruelties to which 
horfes are fubjefted ; and hope the plan here given will at 
leaft afford a ufeful hint for further improvements in this 
line. This machinery will alfo afford l'oine advantages in 
loading carts, where the common length of the cart is too 
fliort for the articles intended to be carried. 
AAA, fig. 17. is the plan of a common town-cart in¬ 
verted. B B, Hiding-bars or levers ; i. e. the horfe-helper. 
C, crofs-bar, or handle of the horfe-helper. D D, fpring- 
fwivels or hooks to receive the ends’ of the ropes FF. EE, 
flops, to prevent overdrawing the ropes. FF, ropes and 
hand-rings to projeft them. G, a prop to prevent hang¬ 
ing the horfe. H H, the bearing-plates of the horle- 
lielper, with pulleys or fhivers attached thereto. I I, 
tranfverfe cavities under the axletree to admit the paffage 
of B B. K, the extra bar for country carts. L L, the 
liandfpikes for ditto. M M, the axletree or fulcrum. 
N N, nn, the hind and fore ear-breadths. O O, the extre¬ 
mities of the (hafts. P, the back-chain. Q, the prop. 
Connefted with fig. 16. is a fcale of feet and ^ parts of a 
foot. 
Fig. 18. a profile view of the improved cart with the 
horfe-helper upon a proper angle to clear the packing- 
hooks, See. The fame letters denote flmilar parts. 
Mr. Snart’s account of his invention is as follows: 
“ As all librating bodies aft in an exaft and direft ratio 
to their elongations from the fulcra, confidered in con- 
neftion with their proportion of weight, and vice verfa 
(the firft refinance by the inequality of their matter being 
excepted), it appears that, as is the folidity of the part of 
the lever relting on the fulcrum to the folidity of its ex¬ 
tremities, fo is its refinance to be afted upon by a weight 
which is lefs than its difproportion ; which inequality of 
power is to the weight added in an inverfe ratio, but di- 
reftly as the diminution. It is evident that the conftruc- 
tion of carts at prefent is very unfavourable to the relief 
of the fallen horfe, who is intentionally placed at the 
longelt arm of the lever (for the (hafts aft as a lever by 
fuppofing the axle-tree to be the quiefcent fulcrum), that 
he may the better refill: the weight of the load, fliould the 
equilibrium be by any means deftroyed ; for any given 
weight upon the hind-part of the cart has lefs than half 
the power of refinance of the horfe ; fo that, if fuch horfe 
falls, this advantage is prejudicial to his being raifed. 
The inventor, therefore, of the horfe-helper, prefumes 
that a plan, the objeft of which is humanity, will fuffici- 
ently apologize for his offering to the public an invention 
which fo obvioufly more than counteracts the before-men¬ 
tioned diladvantages, as may be feen by infpefting the plan 
in connection with its fcale. 
“ Let AAA, fig. 17, be a plan of a common town-cart 
inverted, vvhofe hind ear-breadth, N N, projects iron; its 
fulcrum, oraxletree, MM, 4 feet 7 inches, while thebaclc- 
cbain P is 7 feet 6 inches ; and the extremes of the (hafts, 
O O, which prefs upon the tuggs in the horfe’s collar, are 
9 feet 6 inches. Now, admitting that the horfe who falls 
weighs 15 cwt. and that his bearing is 1 cwt. which is 
16 cwt. it is very evident that it will require 33161b. weight 
grofs at the ear-breadth N N (which is but 4 feet 7 inches 
from the fulcrum MM) to counteraft fuch a weight; 
even admitting that the load had not flipped forward at 
all by the fudden concuflion and depreffion of the fore¬ 
parts of the cart. The efiimate, therefore, now will be 
nearly as follows : 4 feet 7 inches, or 55 inches, to 9 feet 
6 inches, or 114 inches, will give for the weight 33161b. 
which is more than that of twenty-two men, at 1501b. 
weight each, before a difabled horfe can be raifed from 
the ground ; but we know that fix men cannot bear their 
weight with advantage on one of our prefent-made carts, 
without endangering their perfons or clothes, or both ; fo 
that the horfe is left to ftruggle with three-fourths of the 
weight himfelf, and this in a very bad pofture, as he is em- 
barraffed by the (hafts, &c. Hence many horfes, if not 
immediately killed, are at leaft ruined lor ever. The ad- 
vantageof the fliding-leveris in the proportion ofia6 inches, 
the length of the levers at C to 114 inches, the length of 
the fhaft, viz. O O ; and this without the addition of the 
handfpike L L, which gives a further advantage of one- 
fourth. Again, if 55 inches, the length of the lever at NN-, 
require 3316-§^-lV>. weight, what will 126 inches require? 
Anfwer, i447-j 5 5 a ^lb. which is lefs than the weight of ten 
men, at ijolb. weight each. This, however, is not half 
the advantage of the lever, as it affords convenient accom¬ 
modation for more than twenty men, without hazard to 
clothes or perfons. And, if we fuppofe a Aiding bar at K, 
one man (if men are fcarce, as in the country), by apply¬ 
ing the two handfpikes L L, may gain power fuflicient to 
raife his horfe himfelf, efpecially as it fortunately happens, 
that country-luggage very frequently confifts of luch ar¬ 
ticles as might be removed from the front of the cart, and 
placed on the bars C and K; fuch, for inftance, as lacks 
of corn, feed, potatoes, bran, flour, peafe, beans, &c. See. 
which, by being taken from the front, and placed behind, 
would have more than double the advantage of its real 
weight; and, in town, where the luggage is different, af- 
fiftance is always to be obtained from byftanders. 
“ Notwithftanding the ftatement of powers for relief 
which I have here given, it is plain, from daily obferva- 
tion, that lefs than half the power here ftated is only ufed 
in general, as eight or nine men can often (though with 
much danger and trouble) raile the fallen horfe. Hence, 
by ufing the fliding-lever, three or four men, without dan¬ 
ger, delay, or trouble, will he fuflicient. As, immedi¬ 
ately the horfe falls, the driver has only to go behind the 
cart, lay hold of the hand-rings F F, and at one pull the 
whole apparatus is projefted ; then lay hold of C, o.r B B, 
according as the cafe required, and the horfe will be in- 
flantly relieved.” 
Mr. Snart adds, that this apparatus is quite portable, 
colts but little, and adds not more than to the weight 
of the cart. 
Braby’s improved cart and drag was alfo honoured by 
the notice of the Society of Arts, and a compliment of 
five guineas, May 1814. Lord Somerville’s cart-drag has 
been deferibed under the article Husbandry, vol. x. 
p. 593. Plate VII. fig. 7. The prefent machine is ftiowu 
at fig. 19-22 of the annexed Plate. It has props attached 
to it, to aft as a drag, and prevents the fhaft-horfe from 
falling in going down fteep declivities, as, by means of 
fuch props, the weight is entirely taken off the horfe’s 
back, and one or both wheels locked, fo as to aft as a 
fledge, and occafion the cart to defeend a hill with an eafy 
regular motion. The defeent of hills is ufually hard firm 
ground ; and, the fronts of the props being (loped upwards, 
they will readily Aide over (tones, or inequalities of the 
road. In every cafe, where a wheel requires to be locked, 
this prop may be ufed to a greater advantage ; and it may 
