8s'c, Kc, 8s' c.

4)

x-X

PRICE ONE SHILLING AND SIXPENCE,

OBSERVATIONS

ON THE

FORMATION AND USES

OF THE

NATURAL FROG OF THE HORSE *

WITH A DESCRIPTION OP

A PATENT ARTIFICIAL FROG,

\

TO PREVENt AND CURE

CONTRACTED HOOFS, THRUSHES, CANKERS, AND SANfi

CRACKS.

By EDWARD COLEMAN,

i/'

Professor of the Veterinary College, Sic. Sic. Sic .

PRINTED FOR THE AUTHOR,

By J. Crowder, JVarwick-Square ;

AND SOLD AT THE VETERINARY COLLEGE;

At the forges in grosvenor mews, bond-street;

AND LITTLE MOORFIELDS, FINSBURY-SQ.UARE :
ALSO, BY J. JOHNSON, IN ST. PAUL’S CHURCH-YARB,

1800,

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PREFACE.

The principal object of the prefenfc
publication, is to give a defcription of a
patent Artificial Frog, and to point out the
neceffity of its application in the liable
to the natural frogs of horfes, to prevent
and cure contracted hoofs, thrufhes, can-
ker, and fand cracks.

But to demonflrate the utility of an
artificial frog, it is necefiary to defcribe
the ftructure and functions of the natural
frog ; and in this defcription I fhall be
obliged to borrow fome obfervations from
my own work on Shoeing, &c. Unlefs the
ftructure and functions of the froo- of the

O

horfe be well underftood, it is fcarcely
poffible to know the great importance of
preffure to the health of that organ.

If

C ii 3

* ,

If it be a fadl, that the frog is very
generally raifed afyove the furface of the
ground, and that the abfence of preffure
to the frog in the liable is the caufe of
contracted hoofs, thrufhes, canker, and
fand cracks, and that the artificial frog is
capable of giving any degree of preffure
to the natural frogs of all horfes, even
when fhod with the moft common fhoes,
fo as to prevent and frequently cure thofe
difeafes ; then I trufl the patent frog will
be found an important improvement.

Had it been thought as neceffary for
the health of the whole foot that the frog:
fhould have preffure, as it has been hi-
therto confidered expedient to raife the
frog from the ground, then no doubt a
very little obfervation might have fuggefl-
ed the advantages to be derived from an
artificial frog.

But the inventive faculties of thofe who
attended to this fubjedt, were employed in
a contrary diredfion and produced a con-
trary effedt, They fought not how to give

preffure

' . [ iH 1

preffure to the frog of thehorfe ; but hpw
to raife it frqm the ground.

The artificial frogs are fold for three
/hillings each at the Veterinary College ;
alio, at the Forges in Grofvenor Mews,
Bond-ftreet, and Little Moorfields, Fins-
bury-fquare, where they are fitted to the
feet of horfes without any additional ex-
pence.

They are alio fold by the Veterinary
Surgeons who have quitted the College,
and may be had in moil of the principal
towns in the Kingdom.

Observations,

i

V

1

/

-

OBSERVATIONS, &c:

«

nr

X HE natural Frog of the Horfe is placed
in the centre of the foie, externally convex,
and of a wedge-like form, pointed towards
the toe, but expanded as it advances to the
heels. In the centre of the broad part there
is a fiffure, or feparation. The frog is con-
nected internally, with another frog, of a
fimilar figure, but different in ftruCture. The
external frog is compofed of foft elaftic
horn, and totally infenfible. The internal
frog has fenfation and is much more elaftic
than the horny frog; and at the extremity
of the heels is connected with two elaftic fub-
ftances called cartilages. The toe of the fenfible
frog is united to the coffin bone ; but more than
tiine tenths of both frogs are behind the coffin

b bone.

[ 2 ]

bone. The toe of the fenfible and horny frogs,
from their connexion with the coffin bone, are
fixed points, and have no motion ; but the
heefs of the frogs being placed pofferior to
the coffin bone, and in contaft with move-
able, elaflic, (and not fixed or refilling) fub-
fiances, a very confiderable lever is formed,
and whenever the horny frog comes in con-
tact with the ground, it firft afcends, and then
defcends. The preffure of the ground alfo
expands the horny frog, and the fenfible frog
expands the cartilages, and at the heels and
quarters immediately below the hair, totally
governs the direction of the future growth of
the Orufl.

This afcent of the frog, not only by its
wedge-like form preferves the heels and quar-
ters from contraction, but affords to the horfe
an elaflic fpring, and prevents the animal
from flipping whenever it embraces the
ground. Without any anatomical enquiry in-
to its internal ftru&ure and union with other
parts, the fhape and convexity of the horny
frog clearly demonflrates that it was formed to
come into contact with the ground.

We cannot fuppofe that the all-wife Creator
would have made an organ, much expofed to

injury.

2

t 3 1

injury. Without making its tfruatire adequate
to its funftion, Animals deftined for a cold
climate are provided with a much w armer
covering than animals in a higher tempera-
ture: the eye is admirably conftru&ed for
receiving light ; the ear for the vibrations of
found ; and every organ, in every animal, is
beautifully formed to anfwer its peculiar ufe.
Shall we then doubt that the frog is made
with the fame degree of wifdom as other or-
gans ? Shall we not conclude that it was in-
tended to receive preflure, fince its convexi*
ty muft mkke it liable to touch the ground
at every ftep ? The more I invefhgate this
fubjea, the more I am convinced that the ufe
of the frog is to prevent the horfe from flip-
ping, to preferve the cartilages and hoof ex-
panded, and, by its motion, to a& as an elaf-
tic fpring to the animal.

Mr. Saintbel, and many others were of
opinion, that the ufe of the frog, is, to ferve
as a cufhion, or guard to the tendon of the
flexor mufcle of the foot. Where this opinion
prevails, it is very natural to conclude, that
art fhould endeavour to raife the frog from the
ground, by a thick heel’d fhoe, in ordei to
guard the tendon from bruifes. But, if it be

b 2 a truth

[ 4 ] '

a truth that this projecting body was intended
to receive the prcflure of the ground, then it
wiil follow, as a law of nature, that unlefs the

frog performs its functions, it mull become
difeafed .

The human legs are formed to move and
fupport the weight of the body ; but if they
are kept in a horizontal pofture, in a date of
red, the whole machine will foon become en-
feebled and difeafed. The horfe is an animal
intended for aaive life, but if he is fuffered to
remain without motion, not only his legs but
his whole fydem becomes affefted. Indeed,
common obfervation clearly proves, that no
animal, or any part of any animal, where the
natural functions are perverted, can be prefer-
ved in health. If the real ceconomy of the
frog had been equally well underdood, it
would have been thought as neceflary, for the
health of that organ, that it fhould receive
prelfure, as we know It to be important for the
health of the horfe to have motion.

It is therefore as great an aft of violence
to the frog, to raife it from the ground, and
muft as neceffarily produce difeafe, as to de-
prive mufcles of a&ion. (That the frog was
not made to defend the tendon, can be de-
mondrated. There is no medical man, ac-
quainted

[ 5 ]

quainted with the ftruaure and ceconomy of
tendons, but muft be convinced, that the
frogs of horfes are formed for other fun&ions.
It has been proved by experiment, that the
fubftance of tendons in health has no fenfa-
tion; and, confequently, that one infenfible
body (viz. the frog) cannot have been made for
the . purpofe of proteaing an organ void of
feeling. Again, the frog, being made of a
wedge-like form, a great part of the tepdqn
is not covered by the frog, and more than one
half of it projeas behind die tendon. If the
frog had been made to aa as a culhion, tq
fave the tendon, then its fhape and magnitude

would have been exaaiy equal to the ten-
dons.

The praaice of fhoeing very much depends
on the. funaions of the frog being underltood.
It the opinions here advanced refpeaino- its
, eS’ be veil founded, then it mult follow
that paring the frog, and railing it from the’
ground annihilates its funaions, and ultimate-
ly i not immediately, produces difeafe ; and
that expofing the frog to preffure, is the only
proper method to keep ft in health. ' More-
over, it has from experience been afcertained
that unlefs the frog fultainan uniform preffure’
Vhm at T^> heels as well as the L con-’

BS ' tract.

I

[ 6 ]

tra£t, but if that organ be in clofe contact with
the ground, then it fpreads and is free from
Jhjrufhes and canker, and operates' as a wedge
to keep open the heels of the hopf.

The fame degree pf perpendicular preffure*
applied to the infenfible frog, that produces pn-
ly pleafantf nfation to the fenfible frog when in
health, creates exquifite pain when difeafed. It
is therefore of great importance to preferve the
frog found, for when contracted or cut, or in-
flamed, it becomes highly fufceptible of every
impreffion ; we might with as much wifdom
.contra£t the flioe of the human fubjeSt, or re?
move the Ikin of the foot, when obliged tp
walk on Hones without fhoes.

Granite and other hard fubftances, give no
pain to a frog expofed tp conftant preffure in
the Jtahle ; but when above the pavement, it
generally becomes contracted , and the fenfible
frog inflamed, and then on£ ftroke from a pro-
jeSting ftone, will produce pain, perhaps lame-
nefs, while perpetual perpendicular preffure is
attended with falutary effeSts.

Thofe who conceive, that the frog was not

made to come in contact with the ground,

and

* By perpendicular preffure, I mean that preffure th*
frog meets with from the ground, aftd not the lateral
prgffure of a contracted hoof.

i: 7- %

and with that view cut the frog, to diminifli
its convexity, and employ high heeled (hoes
for its protection, would do well to confider,
whether their practice is in truth conformable
to their own principles. If it be true, that no
(hoe, however high at- the heel, applied to
any hoof, can prevent the frog from occafional
prejfure^ then it mull; follow, that the pra&ice
and principles do not agree ; and it is obvious,
that no frog is totally exempt from preffure,
even if the (hoe be turned up two inches at
the heels.

Where the roads are covered with a convex
pavement, or with loofe (tones, the frog is
liable to be (truck by every (tone that exceeds
the thicknefs of the (hoe ; and in other fixa-
tions, where there are no (tones, the cavity of
the (hoe is filled with earth ; fo that the frog,
when the horfe moves, is expofed to unequal
furfaces, and confequently receives frequent
preffure. It therefore becomes a queftion,
whether repeated blows on a part that has
been raifed, on the average, five-fixths of the
twenty-four hours above the ground of the (table,
and from the abfence of preffure made very
(ufceptible of impreffion, will not produce
more pain, and more difeafe, than conftant
and uniform preffure.

b 4

When

r s- r

When a fbarp ftone comes in cental with a
foft and thin frog, horfes are liable to fall.
It may therefore be imagined, that. if a horfe
feels pain from the preffure of one blow, great
mifehief muft enfue, when the fame caufe is
many times repeated ; and that the effe6l or
difeafe muft increafe in proportion to the caufe.
But it has not been confidered, that in con-
fequence of always handing on the frogs on
hard furfaces, in the ftable, thefe organs re.-
tain their natural infenfibility and elafticity,
and refift even the hardeft bodies without the
leaft irritation. Do we not fee that the Ikin of
the palms of hands of fmiths and watermen,
become thickened and callous, and feel no in-
convenience from fubftances that would ab-
folutely blifter a hand, in the habit of wearing
gloyes ? And, is it not a faSt, that the foie of
the human foot is equally void of feeling,
v with thofe perfons who are accuftomed to,
walk without (hoes ? A man obliged to tra-
vel on lharp ftones would not think it pru-
dent to lay up his legs, and give, the, foies,,
of his feet no preffure within doors. If the,
hoof of the horfe was always expofed to na,-
.tural air and moifture, and the frog to ir-
regular furfaces, the form of the lhoe would
be of lefs confequence. But as in the ftaWq
the frog is very generally raifed above the

t 9 ]

ground, the artificial heat tends powerful-,
ly to contraft the heels of the hoof. AVhen
the hoof contracts, the frog muft alfo become
contra-Sled, and inflammation and a fuppura-
tion follows, called a Thrufh. No contraftion,
however, takes place, where the frog is made
to receive conftant preflure, as the {landing
perpetually on that wedge encreafes its growth,
prefles upward the fenfible frog, and expands
the cartilages of the hoof. And as the firft
flioot of the cruft at the coronet is very thin,
the dire&ion of its fibres will be altogether re-
gulated by the width of the cartilages immedi-
ately below the hair at the quarters and heels,
and the cartilages will be always more or lefs
expanded, and the hoof more or lefs circular,
as the frog has more or lefs preflure.

On that principle I long fince recom-
mended a flioe with thin heels, as the beft
formed flioe to bring the frog on the fame
level ; and with great truth I can affert, that,
although in fome inftances, from a fudden mif-
application of the thin heel’d fhoe to improper
feet, I have feen the tendons afte-Sted, yet
from all the experience I have fince had, and
from all that I have feen or heard of the prac-
tice of others, I know of no inftance where
the frog , from conftant preflure, <fid not ex-
pand

[ 10 ]

pand and receive great benefit. Neither is it
true, as has been afferted, that the frogs of
horfes, from the preffure of the ground, arc
made inelajiic , and incapable of motion.
It is as totally contrary to the invariable laws of
nature, that an organ (hould, in confequence
of performing its natural functions become
difeafed ; as it is an invariable principle, that
an organ deprived of its fun£tions cannot con-
tinue in health. I have particularly exa-
mined the ftru&ure of many hundred frogs,
in hoofs fhod with various fhoes, and I have
uniformly found, that in proportion as the
foot is contracted , it becomes hot and in-,
flamed ; and if the frog be not deftroyed by
thrufhes or canker, it is brittle and inelajiic.
But where the frog has been conftantly on a
level with the heels, whatever may have been
the form of the fhoe, or without fhoes, the
hoof remains circular, and the natural form
and elaftic ftru£ture of the frog is preferved.

The inelaftic quality therefore of the frog,
fo far from taking place in confequence of
the preffure of the ground, proceeds wholly
from contra&ion, and contraction from the
want of perpendicular preffure.

Where the frog conftantly meets the ground
in the (table, the heels are open, and the

t 11 ]

frog elaftic, expanded and healthy ; but where
the cavity of the horny frog is contracted,
the fenfible frog is violently fqueezed, and
becomes hot and inflamed, and from this
heat the horn is dry and inelaftic.

Thofe who from falfe kindnefs raife the frog
from the ground, to prevent preflure, will pro-
bably be furprifed at the affertion, that the
fenfible frog fuffers moll pain and mod preflure
when molt raifed from the ground.

It is, neverthelefs, literally true ; for in pro-
portion as the frog is free from perpendicular
preflure, the heels of the hoof contract and, as
the hoof contracts, the frog alfo becomes con-
traced ; and, in proportion to the degree of
eontraSlion, the fides of the fenfible frog, with-
out any refpite, mull receive lateral preflure
from the fides of the horny frog. Perpen-
dicular preflure is natural both to the horny
and fenfible frogs, and the afcent of thofe or-
gans prevents concuflion and preferves them in
health. But nature has made no proviflon for
permanent unnatural preflure, produced by a
contraSlion of the cavity of the horny frog, and
it has certainly not been confidered that the
frog fuffers the greateft violence* and more
preflure, when raifed from, than when in conr
ta£t with, the ground.

Where

[ 12 1

Where the frog is in a morbid ftate, and
unnaturally deprived of perpendicular preffure,
it is feldom fate to lower the heels at once,
fo as to make the frog on a level with the
Ihoe; and, in many cafes, it is not pofiible
with any fhoes, or .even without {hoes, to
give the frog preffure on fmooth furfaces;
much lefs is it practicable for the frog to reft
on the ground when fhod with common thick-
heeled {hoes. In the {table, therefore, while
at reft, the frog is generally railed above the
ftioe, and as preffure is effential to its health,
particularly when the hoof is expofed to heat,
it appeared to me of great importance, in all
cafes where the heels of the ftioe and the fro^
cannot with fafety be made on the fame level,
to apply an artificial frog, to fit and give any
degree of preffure, in the liable, to the natural
frog, with any {hoes. With that view, I firft
employed plaifter of Paris, but from its tender
texture, that application was found to fail, and
Mr. Ridfcvord, a very intelligent pupil of the
college, propofed to employ leather, and to.
conned! it with the ftioe by firings. This plan
alfo did not fucceed, but I think it a duty due
to Mr. Riclfword, to mention, that in the con-
ftrudtion of the artificial frog, I have received
confidcrable afiiftance from his attention and

ingenuity.

[ 13 ]

ingenuity. While the horfe is in motion, and
the hoof expofed to unequal furfaces, the ar-
tificial frog fhould be removed, as the natural
frog, out of the liable, will receive frequent
prefiure with any Ihoes ; but that period is of
Ihort duration, when compared to the length of
time the horfe remains at rell, and the frog
raifed from the ground.

Artificial prefiure is moll particularly wanted
tvhen the heat of the liable operates powerfully
to contract the hoof. In all cafes, therefore ,
i.che/ e the pavement of the fable does not touch
the natural frog, an artificial frog is necejf'ary
to reff contraction of the hoof, thrulhes, and
canker. Sand-cracks, alfo, very generally arife
from a contracted hoof, and may be prevented
by the artificial frog.

If the frog does not abfolutely *eft on the
pavement, whatever Ihoes are employed, the
hoof in the liable will be as muck difpofed to
contract, as it the frog was raifed any greater
diltance. I wilh this fa£t to be well conib
deredi for it has been fuppofed that Ihoes
with a fiat feat, without prefiure to the ffo»,
vvill prevent contraction. But I am fully con-
vinced that neither thick nor thin heeled Ihoes,
where the frog is raifed above preffurc, and
expofed to the heat of the fable, can prevent

contraction

[ H ]

contraction, or its effeCts ; and where the frog
receives that preflure, the heels cannot contraCt
even with the moft common fhoes. For very
obvious mechanical reafons, a wedge in the
centre of the heels, aided by the preflure from,
below, muft be belt calculated to preferve
them expanded, or when the heels are con-
tracted, to force them open. The heat of the
(table in all cafes tends to contraction of the

hoof: but with common fhoes there is no pref-
fure on the wedge, or other caufe to counter-
act that tendency. The artificial frog, whigh
is intended to cover and give any degree of
preflure to the natural frog only, is made of
iron. In order to fit the natural frog, it is re-
quifite to afcertain its width, the length of the
foot, and the diftance between the lower fur-
face of the (hoe and the frog. But if the arti-
ficial frog be too long, the toe, which is flat and
thin, may be fhortened ; and if the heels of the
fhoe are higher than the artificial frog, nothing
more is requifite than to introduce a quantity
of tow between the natural and artificial frog,
fo as to raife it equal or above the level of the
(hoe. I have afcertained by experience, t at
no inconvenience takes place by railing the
artificial frog even one quarter of an inch above

the Aloe i but in ordinary cafes, it fhould no

project

[’ 15 ]

projeCt more than one fixth of an inch above the
furface of the Ihoe. It may, however, be
imagined, that fo much perpendicular pref-
fure to the frog would retard rather than in-
creafe its growth. But the very reverfe is the
faCt : for as the frog', when long elevated above
the ground, is very generally contracted, this
unnatural lateral preffure excites inflammation
of the fenfible frog, and deprives in a great
degree the blood veffels of the power of fe-
creting hom. When the horny frog is expofed
to perpendicular preflure, it gives health, and
not difeafe, to the fenfible frog. The blood
veffels fecrete their due proportion of elaftic
horn, and then the cavity of the frog is pre-
ferred, expanded, and fully equal to contain
the fenfible frog, without the fmalleft degree of
lateral preffure.

It therefore follows, that perpendicular pref-
fure encreafes the bulk of the frog ; while its
abfence from the ground produces contraction,
and leffens its growth.

Neither is this faCt in any refpeCt peculiar to
the frog of the horfe. The cuticle, or outer
Ikin of the human feet and hands, always
grows in proportion to the quantity of preffure.
Thefe parts grow from within outwards, and
the blood veffels will be ftimulated to fecrete

more

[ 16 ]

more or lefs horn, or more of 'lefs fkin, a§
they receive preffure.

The veffels of the (kin of the hand, or of the
fenfible frog of the horfej that have but little
preffure, will produce only a very thin and
delicate covering. Give more preffure, and
nature will furnilh an adequate quantity of in-
fenfible matter to protect thofe parts from in-
jur}'. The toe of the artificial frog is intended
to be inferted under the toe of the fhoe. This
effectually fixes the frog forwards, and to pre-
vent backward or lateral motion, an irregular
groove is made in the iron frog, to receive a
correfponding piece of fteel, placed under
the heels of the fhoe. In general it is necef-
fary to fix the frog more firmly, and, for that
purpofe, a hole is neceffary, made in the
heel of the artificial frog, to receive a ftrap, and .
to buckle at the outfide quarter below the co-
ronet. And that the artificial frog may give
preffure in all cafes with (hoes thickened, or
turned up for hunting or froft, a variety of frogs
are made, to be adapted to particular feet and
particular fhoes. In cafes of thruflies and cam
ker of the frog, where no remedies without pref-
fure are likely to be forviceable, an aftringent
thrufli powder may be applied between the natu-
ral and artificial frog. And in contra&ed hoofs;
(or what has improperly been termed chefl

1 foundered,)

- ; N [ ]

foundered,) where it may not be advifableto lower
the heels equal with the horny frog, the artificial
frog is effentially neceffary. — But indeed in eve-
ry horfe where the fhoe and frog on a fmooth
furface are not on the fame level, whatever
lhoes may be ufed, the iron frog in the liable
fhould be applied, and in order to fix it with
facility, the fpring fhould firfl bejplaced un-
der the fhoe and brought backward to the
heels of the hoof.

The toe of the iron frog fhould then be in-
ferted under the centre of the fpring, and pufh-
ed as far as the toe of the fhoe, while the other
hand confines the fpring until the centre of the
fpring meets the centre of the groove. The
flrap may then be buckled. And to diflodge
the fpring and iron frog, after the flrap is un-
buckled, nothing more is requifite than a fmall
horfe picker, introduced into a hole at the
bottom of the groove of the iron frog ; and the
fpring being raifed above the groove and carried
gently forward, the frog may be withdrawn from
under the fhoe without the fmallefl difficulty.

It may be proper to add, that there is no
caufe of lamenefs from common fhoeing fo fre-
quent as contraction of the hoof and frog, and
as thofe difeafes are productive of violent pain
•to the animal, itmufl afford great fatisfaCtion

C to

[ 18 ]

to the mind of every humane man to be in-
formed, that by the affiftance of a fumplc
machine, that perpetual torment under which
fooner or later mod of the horfes of this coun-
try labor, may be effeaually prevented. A
iboe too fmall for the human foot gives con-
fiderable pain, even when worn for a thort
period, biH.the hoof of the horfe when the frog
has no perpendicular preffure, every day be-
comes more and more contracted, and gives
more and more lateral preffure to the feniible
parts of the foot, and with this permanent pain
the horfe is frequently obliged to fupport ad-
ditional weights. Perpendicular preffure on
the frog, preferves not only the fiog, but the
whole-hoof of the fame form as it comes from the
hands of the Creator.' Neverthelefs there are
many perfons who doubt the good efledts of thin
heel’d {hoes, or of bringing the frog in any cafe
on the fame level with the ihoes. hut fince my
publication on the foot of the horfe, longer ex-
periencehasnot altered, but confirmed my opini-
on on that fubjedt ; and under the circumftances

and precautions already pointed out in that work,

I do not believe it poffible for my judgment
to waver. — I beg therefore to be clearly under-

ftood, that in all cafes where the frog and the

heels

[ 19 1

heels of the Jhoe tire placed on the fame level,
the patent frog is nnnecefary . But where
the frog is final], or the paftern joint long,
or the action of the animal high, or the heels
totf, fo as to render the application of thin
heel’d Ihoes improper, or when the frog from
any caufe is raifed above the ground in the
ftable, an artificial frog is ufeful in all fuch cafes,
and neceffary to refift contraction of the hoof.
But if thin heel’d {hoes were productive of
mifchief, or if my opinion had milled me to re-
commend in all cafes thick ihoes to protect the
frog from injury, (till my prefent opinion, as to
the neceffity of giving preffure to the frog in the
fable , when at reft and expofed to heat, would
ilill be the fame. Whatever may be the thick-
nefs of the (hoe, there are ftones ftill thicker,
and to enable the frog when in motion to bear
fuch preffure without pain or mifchief, and to
refift the influence of heat, and to keep the
hoof and frog expanded, perpendicular pref-
fure to the frog in the ftable muft be always
beneficial, do raife the frog from preffure when
at ref, and yet to expofe it to (harp and hard
bodies when combined with force and con-
ftant afition, muft be obvioufly definitive to
the ceconomy of the whole foot, and to the
fenfible parts in particular.

c 2

It

[ 20 ]

It therefore follows, that whether it be pro-
per or improper for the frog to touch the ground
while in motion, no one with any propriety can
doubt the neceffity of giving preffure to the frog
when at perfeft reft and expofed to artificial
heat.

EXPLANATION

explanation

the PLATES.

FIGURE THE FIRST.

A view of the natural hoof of the Horfe, of
a circular (hape.

aaa The external furface of the foie of a
concave form.

bbb The inferior edge of the cruft.

c c

The jun&ion of the bars with

the cruft.

dd

The points of the bars.

of the cruft

e e

The foie between the heels

and bars, the feat of corns.

ff

Two cavities between the fides of the bars

and the Tides of the cruft.

g

The toe of the frog.

hh

The heels of the frog.

• •
i i

The cleft between the heels

of the frog,

the feat of thruflies.

i

c 3

FIGURE

[ 22 ]

FIGURE THE SECOND.

A view of the hoof with contraCred heels,
produced by railing the frog above the prelfure
of the pavement in the liable,

a a a The foie.

b b The original feat of the bars, but im-
properly removed by the farrier,
c c The original feat of the cavities between
the bars and cruft, but now from con-
traction a folid horn.

d cl The heels of the frog very much com-
prefled, by the contraction of the hoof.
e e The width of the hoof at the heel, not
being more than one half of the length
from f to g.

f The extremity of the heels of the frog.
g The toe of the cruft.

FIGURE THE THIRD.

A view of the patent frog, made of call and
wrought iron.

a a
b

The lower furface oppofite the ground,
formed of call iron.

An irregular cavity for the reception of an
elaftic fpring. Fig. iv.*

The

* In the fore part of this cavity there is an opening for
the point of a picker to remove the fpring, butwhich has
been omitted in the plate of outlines.

[ 23 ]

C The toe of the patent frog, formed of
wrought iron, to be occelionally fhortened
and adapted to the length of the foot, and
placed under the toe of the fhue to confine
the artificial frog from moving forwards.
d d A hole in the heels of the iron frog, for
the paffage of a ftrap to buckle at the out-
fide quarter or coronet.

FIGURE THE FOURTH.

A view of a flat fteel fpring to fix the artifi-
cial frog.

a An irregular projection, to be received
into a correfponding concavity in the
patent frog.

b b The ends of the fpring, to be placed un-
der the heel’s of the flioe oppofite e e, in
Fig. 1.

FINIS.

Printed by J. Crowder, Warwick Square,

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