A TREATISE
ON THE
TEETH OF THE HORSE.
Chapman and Co. St. Mary Axe.
A
TREATISE
ON THE
TEETH OF THE HORSE,
SHEWING ITS AGE
BY THE CHANGES THE TEETH UNDERGO,
FROM A FOAL UP TO TWENTY-THREE
YEARS OLD;
ESPECIALLY AFTER THE EIGHTH YEAR.
WITH COLOURED PLATES, AND A TABLE.
TRANSLATED FROM THE FRENCH OF
M. GIRARD,
DIRECTOR OF THE ROYAL VETERINARY SCHOOL AT ALPORT,
BY
T. IRWIN GANLY,
FORMERLY A PUPIL AT THAT SCHOOL, AND VETERINARY SURGEON TO
THE llTH LIGHT DRAGOONS.
LONDON:
PUBLISHED BY SHERWOOD, GILBERT, AND PIPER,
PATERNOSTER ROW.
1829.
TRANSLATOR'S PREFACE.
In undertaking- the present Translation, which
I am induced to do, as a token of g-ratitude to
the Editor, I trust it will be found acceptable as
well as hig-hly useful to the Profession, and the
admirers of the Horse in g-eneral. I have to
state, that having* been some years in habits of
the closest intimacy, not only with the late la-
mented author, in whom the Profession has lost
one of its brig-htest ornaments, but also with the
father, who has edited the present edition, and
to whose kind attention and instruction conjoint-
ly, I owe whatever knowledg-e I possess in the
Veterinary Art ; and having" moreover, during*
my studies at the Royal Veterinary College at
Alfort, promised both father and son that I
would translate into the Eng-lish languag-e (and
g-et published, if possible) the former's very
valuable work on the Anatomy of the Horse,
&c. being-, as I consider, by far the best system
on that subject, and the only one as deserving*
that name, which has hitherto appeared ; and I
am now most happy to say, that having- very
nearly completed the translation, I shall shortly
be able to perform that promise, and which
would have been accomplished ere this, but for
my time having* been much employed in prepar-
ing" to join my regiment now in India.
vi
translator's preface.
I do not consider that there is any necessity
for apolog-ising" for attempting* this translation,
further than by simply stating- the fact, that
there is not in the Eng-lish language, as far as
I have been able to learn, any work that appears
to convey correct ideas, or useful information
on this subject, at least beyond the eig-hth year
of the horse's ag-e. Mr. Percivall has certainly
g-iven a short sketch in his book, as from Pes-
sina, and also from a little French periodical ;
and he has, if my recollection serve me rig-ht,
added some remarks of his own, which so far
as his opinion g-ces, would throw very complete
discredit on them : tliis, I apprehend, must have
arisen, either from Iiis not having- paid sufficient
attention to the subject, and consequently not
clearly understanding- il, or from prejudice; the
latter of which I should be sorry to suspect him.
On my own part, I have for several years
past, in a very extensive practice, paid great
attention to the subject, and I can fully confirm
the correctness of the principles laid down in
the following- work.
The great necessity for an useful treatise on
this subject, I believe few persons will deny,
when they consider that by the present mode in
general use in England of judging the horse's
age, after the teeth are completely changed, ex-
tend to only three years of the most useful period
of his life ; — viz. from five to eight years old ;
TRAJfSLATOR's PREFACE.
vii
and in addition to tlie many recorded instances
of a long-er life in the horse than is commonly
met with, I can adduce the following* in one of
my own, and the best I ever possessed, whether
in the field or on the road, and which I bought
when he was twenty-two years old : this I clear-
ly ascertained afterwards from the person who
bred him ; and after this he v/as hunted hard
three seasons, as well as rode as a hackney
during- the summers.
The numerous mistakes I have seen made as
to the ag-e of horses, by those persons who ought
to have known better, and some of whom would
be considered as high authorities even in the
Profession, have long- since convinced me of the
necessity for having some better data than those
in general use : I have, it is true, heard of a
gentleman in extensive practice, who asserts,
that he can tell the age of any horse to within
a fortnight ; but if my information be correct, I
am quite certain that he must be one of two things
which shall be nameless ; and to my own know-
ledge, he has been more than two years mista-
ken in a horse's age.
When I observed a work on the age of the
horse, by Mr. Bracy Clark, announced, and,
judging from his other learned and truly scien-
tific essays, connected with the horse, as well
as from his having been the first person to de-
monstrate the elastic nature of the horse's foot,
vjii
translator's preface.
and (as I have since learnt) to whom we are
indebted for the only true principle of shoeing,
if the various plans now in use deserve the name
of principle, I was consequently led to sup-
pose, it would supersede the necessity of another
work on this subject, and that a translation of
M. Girard's Essay would not be wanted; but
on perusing" it, I found little or nothing new,
and, with the exception of that part which re-
lates to the composition of the teeth, he has only
presented us that with which nearly every per-
son acquainted with horses was already familiar.
I cannot conclude without expressing* my g-ra-
titude to the memory of my lamented friend, the
author of the following" pag'es, whose urbanity
and politeness were only equalled by his high
professional attainments, and the readiness with
which he gave explanations, and communicated
information ; and it ever appeared to alford him
the highest gratification to advance the studies,
and smooth the path for those around him. As
to the father, his high professional merits, so
laboriously and perseveringly acquired, have
placed him above any eulogium of mine, how-
ever deeply I am indebted to him for whatever
small share of professional knowledge I may
possess.
T. mWIN GANLY, V. S.
May, 1829. Hth Light Dragoons.
EDITOR'S PREFACE.
The Treatise on the Ag-e of the Horse, published
in the Recueil de Medecine Veterinaire, for Ja-
nuary, February, and March, 1834. The co-
pies which were taken separately at the time of
the first impression, had a rapid sale, and had
been all sold at the period of the fatal event
(October 1825) that deprived me of an only son,
on whom I had rested my fondest hopes, and
who had already greatly distinguished himself
as an Anatomical Professor and Teacher. I
have been strongly solicited to reprint that pro-
duction, at the same time to make such additions
and alterations to it as might appear necessary
to me. All solicitations had been vain, if the
idea of honoring the memory of him who ought
not to have preceded me to the tomb had not de-
termined me on undertaking this labor.
It" is not my province to point out whatever
merits the little work may have, which was one
of the first attempts of the author, and which
has been spoken of with commendation by one
of the distinguished Professors of the Royal
Veterinary School of Alfort.* I shall only say
* See the account of the labors of the Royal Veterinary
School of Alfort, during the scholastic year from 1825 to 1826.
A
2
EDITOR'S PREFACE.
of this little work, that it has been favourably
received ; that it includes all the new observa-
tions since the days of La Fosse ; and that it
represents the present state of our knowledge
on the subject of the age of the horse. The re-
marks that I have had occasion to make in the
course of my anatomical labors, on the changes
the teeth undergo after eight years of age, in
consequence of wear, and a succession of years,
are pretty nearly all included in the text of this
tract. Since 1824, 1 have not given my attention
to any new researches, nor have I collected any
particular ideas relative to the distinctive signs
of the age. This edition has however undergone
corrections, particularly the descriptive part, in
which there had been a good deal of negligence*
I have also made some additions which have ap-
peared to me as useful and necessary to increase
the interest of this Essay. The two Plates
placed at the end of the text, to facilitate the
understanding of the rules laid down, and
which were not in the first edition, were executed
under my own eye, from the pencil of M. Rigot,
head of the anatomical labors at the Royal
Veterinary School of Alfort.
Having been intrusted in 1806, by the late M.
Tenon of the Institute, to make researches of
the wear of the teeth in the larger domestic her-
bivorous animals, I conceived the idea of a work
on the different alterations that these parts un-
editor's preface.
3
derg-o. M. Tenon approved hig-hly of this
project, and marked out to me the course I
should pursue to attain my object with more
certainty ; and at the same time communicated
to me numerous remarks that he had made on
the diseases of the teeth, and on their false wear.
From this period I occupied myself in collecting
all the anatomical specimens that presented any
peculiarities relative to the subject that I pur-
posed to treat of. In some years my collection
became numerous and important : it embraced
all the domestic quadrupeds ; the most interest-
ing" preparations of these were those relating* to
the study of dentition. Nearly eig-ht hundred
pairs of ends of jaws, mounted on small pieces
of board, (according- to a new method*) belong-ed
to the horse tribe. Amongst the rare and cu-
rious specimens, I shall mention first three or
four horses' heads, in which different molar
teeth were transformed into hard black bodies,
without any determinate org-anization ; — second,
the head of a mare, in which the upper molai-
teeth on the rig-ht side did not wear, except on
the inner side, and their external surfaces were
of a prodigious length. — Third, another head
of a mare, whose upper incisor teeth came fur-
ther forward than those of the lower jaw, which
* I have presented two specimens to Professor Coleman
of this extremely ingenious mode of mounting the jaws,
which very much facilitates the study of the age, and occu-
pies very little room. Tr/Vnsl.
4
editor's preface.
had perforated the palatine surface of the small
super-maxillary bones — Fourth, a considerable
number of jaws of horses and dogs, having* su-
pernumerary teeth, &c. &c.
The occupation of the School of Alfort by
foreign troops in April 1814, caused the dis-
persion of this collection that had cost me so
much labor and care : this circumstance did not
a little contribute to make me abandon my ori-
ginal project, which I could not otherwise pur-
sue than by re-establishing the specimens that
were destroyed or altered : embarrassments of
different kinds did not allow me to undertake
such re-establishment ; but it became the task
of the son not to allow the fruit of the labors of
the father to be lost.
Motives, which it is useless to relate here,
placed me in 1811 under the necessity of finding
a date for some new observations on the organi-
sation, growth and wear of the incisor teeth of
the horse. For this purpose I addressed a let-
ter to M. Tessier of the Institute, which he
caused to be inserted in the forty-sixth volume
of the Annals of French Agriculture. I chiefly
endeavoured to make known the difterent shades
that the teeth present after the obliteration of the
mark, to prove, in opposition to the generally-
received opinion, that the horse carries indica-
tions of his age as long as he lives, as well as
that it is implanted in the maxillary socket.
editor's preface.
5
In the early periods of its formation, the in-
cisor of the horse resembles a cellular body, the
thin sides of which are soft and membraneous,
and promptly become hard and thickened, be-
coming- reflected at the side of the table. This
first dental production g-ives rise to two cavities
that have no communication with each other, and
differ most essentially ; the larg-est being- situ-
ated next the root, C See plate ^st, Jig. 16, J
contains the pulpy substance, whilst the outer
cavity is open at the side next the table, form-
ing* a reflected funnel.
This same dental production becomes trans-
formed into enamel, which is quickly surrounded
by the bony substance on both its surfaces ; the
latter incrusts itself in greater quantity on the
side next the root, and never completely fills the
funnel, the cavity of which does not become ob-
literated but by the effect of wear. The funnel
is formed, as has been just stated, by the re-
flection of the elementary membrane of the tooth,
and forms a g-enuine septum or partition, ac-
quires a certain leng-th, and terminates in a
rounded blind pouch.*
In consequence of wear, the enamel of the
incisors is divided into two portions, the one
exterior or casing- enamel, the other interior and
* The incisor teeth of the other domestic quadrupeds,
beside the monodactyls, or single or solid footed, have not
any dental funnel, but only present rudiments of it, like
the tushes of the horse, and the incisors of the ox.
A 3
6
editor's preface.
central, which surrounds the funnel. Being-
harder, and presenting" more resistance than the
bony substance that surrounds it on all sides,
the central enamel forms a slight prominence,
and takes on different forms, in proportion as
the funnel becomes destroyed and narrowed.
These different anatomical considerations, which
I merely mention, and which are capable of the
most useful application to a knowledge of dis-
tinguishing the number of years that the animal
has lived, will be found more amply explained
in the text of this treatise.
The age is, of all knowledge of the horse's
exterior, the part to which amateurs of the horse
more particularly apply themselves, whether
the animal be for pleasure, for labour, or as an
article of commerce ; it is also one of those points
upon which opinions do not always agree, and
which give rise to several disputes, when they
usually have recourse to a veterinarian. In fact,
a pupil, when he quits the school, is not only
called upon to treat and cure diseases, but is
also consulted on the choice and purchase of
these animals. Medical and surgical knowledg-e
is not then sufficient for him, it is also necessary
that he should be able to distinguish all the ex-
terior signs that characterise beauty and good-
ness, or that prejudice the solidity and duration
of his services : he should be acquainted with
all the shades capable of marking the annual
periods of the life of the individual : he should
editor's prej'ace.
7
especially know how to appreciate the different
anomalies that occur, and to form the necessary
approximations ; and finally be able to draw
correct conclusions as to the number of years
that the animal has lived. The want of positive
and correct ideas on these important points, may
expose him to disagreeable contradictions, to
injure his reputation, and even to lose it altoge-
ther in the public opinion. By dint of expe-
rience, habit, and practice about horses, many
men acquire, without any preliminary study, a
particular tact, that enables them to judge
promptly and correctly to the very bottom of the
subject. Some even arrive at a power of cor-
rectly distinguishing the age up to eight years
old. This knowledge is in truth but practical
and empirical, but it is sufficient to expose the
ignorance of the veterinarian who has formed an
erroneous opinion, either from a want of a suf-
ficient quantum of instruction, or who, from his
experience being limited, is unable to apply the
principles that he has been taught.
The successive changes that the incisor teeth
undergo throughout the whole course of life,
form, without doubt, the most certain chrono-
meter to mark the number of years of the diffe-
rent large quadrupeds ; the other external signs
are neither so striking, nor so little liable to
variation, and they can merely indicate the ex-
treme periods of life. Thus, in youth, or rather
at the age of a foal, it presents a physiognomy
8
EDITOR S PREFACE.
that is peculiar to it ; its motions are in g-eneral
quick and lig-htsome, the body is supple and
fat, the skin tight and soft ; the shapes appear
clumsy for want of the proper developement of
the bones. During- the first years of the foal's
life, the head has an agreeable shape, the fore-
head broad and flattened, and the occipital pro-
tuberance pronounced ; after the falling of his
sucking incisors, the head becomes deformed
and heavy, the maxillary bones become insensi-
bly enlarged, the sub-maxillary spine becomes
depressed, &c. The prominence of the orbitary
arcades, as well as the zygomatic spine, the
deepening of the depressions and sides of the
muzzle, the wrinkles of the skin in different
parts of the body, the existence of thick hairs
about the eyelids, the nostrils, and the mouth,
most certainly betoken the weight of years. But
these different signs of youth and age are so
uncertain, and undergo so many variations,
that they cannot be of any utility in appreciating
the number of years that an animal has lived.
The knowledge of the age of the horse by an
examination of his teeth, goes back to a very
remote period, since the ancient writers speak
of it as of a thing known long before them. Both
the Greeks and the Romans knew perfectly well
that the horse's teeth were forty in number, and
the mares thirty-six perfect, that the incisors
were temporary, and replaced by others from
thirty months to five years old, that the tushes
EDITORS PREFACE.
9
or angular teeth appear from four to five years
old, that at eig-ht years old the mark is oblite-
rated in all the incisors, that is to say, the horse
has lost his marks.
The ancients had also remarked some of the
changes that the teeth undergo after eight years
old. In the extracts from the Greek authors by
M. J. Jourdin, we read the following passage:
At the end of the eighth year we begin not
" to distinguish any thing more of the precise
" age of the horse, but perfectly to distinguish
" old age ; we remark in the canine teeth or tush-
" es, which during youth were long and sharp,
" are in old age worn and stumpy, particularly
" those of the lower jaw, and are by this time
" marked by a slight blackness in the middle,
" which lasts, according to the observations of
some persons, until the twelfth year, when the
" teeth begin to slant outwards, and to become
" thickened on the inner side."* Later writers,
such as Solleysel, Garsault, La Fosse, Bour-
gelat, Sind, Brizelius, Brugnone, Walstein,
Pessina, Fechner, &c. have done little more, if
we may say so, than comment, more or less ex-
tensively and diflerently, and apply the remarks
of the ancients ; but none of them have taken
notice of this little blackness, which, according
to Jourdin, shows itself, after the obliteration
* " The true Knowledge of the Horse, his Diseases, and
their Remedies," by J. J. D. E. M. 1647, page 10.
10
editor's preface.
of the mark, in the middle of the table, and sub-
sists up to twelve years old or thereabouts. This
blackish mark was evidently produced by the
dental funnel, which puts on particular shapes,
and disappears at about twelve years old.
The first period of the ag-e of the horse, that
of the gnomonia of the Greeks, and which ex-
tends to eight years old exclusively, and mark-
ed by the first appearance and replacement of
the incisor teeth, and by the obliteration of their
external cavity, the period which follows and
continues for the rest of life, also present two
distinct epochas, the wear of the dental funnel,
and the wear of the portion of the tooth next
the root. During* the first of these two last pe-
riods (the wear of the funnel) the table of the
incisor teeth bears in its middle the central ena-
mel, and the funnel, at first transverse from side
to side, becomes successively triang-ular, oval,
and round. After the disappearance of the
central enamel, the table presents a colored
point, that appears before the wear of the fun-
nel is completed, and takes different shades and
different shapes : it is not even uncommon that
in very old teeth this root gives place to a small
black cavity.*
In studying well all that these marks present
remarkable, produced by the funnel and its
* See the letter inserted in the Annals of Agriculture^
Vol. 46.
editor's preface.
11
root, in noticing" exactly the appearance and
duration of each of these chang-es that it under-
g-oes, we may disting-uish old subjects by prin-
ciples nearly as certain as those founded on their
first appearance, and the obliteration of the
mark in them. Besides, the direction of the
teeth, and the shape of their table, furnishes
important approximations to rectify variations ;
and these approximations become particularly
useful after the destruction of the dental funnel,
for its root is not always very pronounced, or
perfectly distinct. Professor Pessina, of Vienna,
explains the g-radations of years beyond eight
years old uniformly by the shapes that the in-
cisors put on, according" as they wear : he has
disting-uished four successive periods, the oval,
the round, the triang-ular, and the biang-ular.
His considerations are very extended, and per-
haps too minute; are capable of acquiring*
much g-reater importance, and exhibiting* more
accuracy, if he had paid attention to the marks *
that remain after the obliteration of the marks ;
and if he had established all the points of com-
parison that could lead him with more certainty
to the truth. In this present treatise, we have
made all the approximations, and the deductions
have been founded as much on the shape and
direction of the teeth, as on the different shades
of the central enamel and its root. The author
has entered into all the details proper to enable
12
EDITORS PREFACE.
US to well appreciate the principles by which we
are to be g-uided for distinguishing the ag-e. If
it has not attained the degree of perfection which
such a work is susceptible of, it will at least
have the merit of having* placed it in a fair way
for new researches.
HIPPELIKIOLOGIA:*
OR THE KNOWLEDGE
OF THE
AGE OF THE HORSE.
It is only within these few years that we have
possessed any tolerably exact knowledge of the age
of the Horse after his eighth year ; previous to
which, habit, or a more or less erroneous routine,
was the only guide ; of course embracing numerous
errors. Thus this branch of veterinary knowledge
was found exactly in the state in which it was left
by Aristotle, Varro, Columella, Absyrtes, Vegetius,
and all the other ancient authors. L. Rusius,Tacquet,
Ruini, Garzoni, and SoUeysel, hardly added any
thing to what was already known as to the manner
of organization, the formation, the appearance, or
the wear of the teeth ; we are even only indebted to
modern authors, such as Gueriniere, Garsault,Bu{fon,
and Bourgelat, for having exposed the folly of cer-
tain opinions ; they no longer believed that the folds
of the skin, or the number of processes of the bones
of the tail, were indications of the age ; but very
properly confined themselves to an examination of
the teeth ; they however stated nothing new ; in
fact they possessed only empirical notions as handed
down from the first Hippiatrists.+
* From three Greek words — Hippos., a horse ; elichia, the
age ; and logos, a discourse.
+ From two Greek words — Hippos , a horse; and iatros, a
physician. Trans.
B
14
AGE OF THE HORSE.
The observations of Tenon* placed those of Ruini,
on the three first molars being temporary, beyond
all doubt, and in demonstrating the true cause of
the wear of the teeth, induced Lafosse to think that
the form of the incisors ought to be at all periods
of life one of the most certain indications of the
age that we could consult ; but he did not profit by
this happy idea, and even alluded to it so slightly, .
that few veterinarians know of his having mentioned
it.f Professor Pessina has fallen into the opposite
extreme : he attached a great deal too much import-
ance to the different shapes that the incisors take,
and put forward as facts, remarks, of which experi-
ence does not always prove the strict correctness.
However, the work of Pessina is, without doubt,
notwithstanding its prolixity, and the minuteness of
its researches, the best that we possess on the age
of the horse. It is necessary always, to distinguish
amongst his numerous observations, those that are
correct, from a greater number that are merely the
fruit of the imagination — this we have for some
years past endeavoured to do. The study of the
funnels of enamel of the incisors, pointed out by the
elder M. Girard, in his letter to M. Tessier,! has
also formed a part of the subject of our observations,
which, if they are not sufficient in all cases and
under all circumstances to avoid error, we hope,
present more correctness than any of the treatises
that have been published on this subject up to the
present time.
* Memoires dc I'lnstitJit, tome ler 1797.
+ Manuel d'Hippiatrique.
X Annales d' Agriculture, tome xlvi. — Traits d'Anatomie
VeLeriauirc, tome It'i". 2^ edition.
AGS OF THE HORSE.
15
ARTICLE I.
GENERAL DESCRIPTION OF THE TEETH.
The Teeth are very hard, bone-like instruments
of mastication, inserted more or less deeply into
and exactly filling the alveoli or sockets of the max-
illary bones, from whence they project in such way,
that the superior and inferior come in contact. In
the manner of their formation they present some
analogy to horny productions, and they resemble
bones in their physical and chemical properties.
Ranged one after the other, on the alveolar edge
of the maxillary bones, the teeth form in each jaw
a curved, parabolical line, called dental arcade ^ the
superior of which is broader, stronger and longer
than the inferior. Each arcade is composed of two
rows of teeth, interrupted towards the anterior
fourth, and united inferiorly into a semi-circle.
In the horse species, we reckon from thirty-six
to forty-four teeth, distinguished into incisores,
intended to incise or cut the food; angulares, tushes,
or laniaria,^ because carnivorous animals use them
to tear ; and molares^ that grind the food as between
two mill-stones.
All the teeth are first formed in the interior of the
maxillary bones, from whence they push out after
having acquired a certain size, and having destroyed
or caused the absorption of the exterior table of
their sockets. Some appearing shortly after birth,
are called sucking teeth ; they are also called /teta/
* Laniarium, a butchery or slaughter-house, from the
verb laniOf meaning both to butcher and to tear. Transl.
B 2
16
AGE OF THE HORSE.
teeth ; but more properly temporary ; these are
the incisors and the three first molares. The for-
mation and appearance of the others are later; they
are called permanent. Finally, those that succeed
the temporary, and take their place, are called
replacers or horse teeth.
1st, INCISORES, OR INCISIVE TEETH,
These teeth are six in number: they form the
anterior or inferior extremity of each dental arcade,
and in young horses, they represent a tolerably re-
gular semicircle, from which they depart as the
subject advances in age.
The two anterior or middle are called nippers^
(medii) which name they undoubtedly take from their
situation so well adapted for nipping. Those placed
at each side are colled dividers (proximi ;) finally
the two last that form the extremities of the semi-
circle are called corners (angidares.)
Each permanent or horse incisor, when it has
completed its growth, or in other words has pushed
out to its full extent, and before it has undergone any
wear, presents two portions for our consideration ;
viz. the free part, or that which is out of the gum,
and the root, or that part which is embedded in it,
and the jaw: — the first, which protrudes from six to
eight lines beyond the edge of the gum,* is flatted
* Six to eight French lines are about equal to from seven
to nine English, or from rather better than half to three
quarters of an inch. Transl.
AGE OF THE HORSE.
17
from front to rear, and represents a cone the base of
which is the table of the tooth, and whose apex is to-
wards the edge of the socket. By this arrangement
the incisors, at first, only touch at the corners of the
table, whilst, towards the socket they leave a space
between them that is filled up by the gums and the
partitions between the sockets.
The anterior or outer surface is slightly convex,
and has two deep longitudinal channels, generally
more remarkable in the incisors of the upper than in
those of the lower jaw, and which increases gradually
up to a certain age. The posterior or inner surface,
{See plate Isf, fgure 11.) is a little concave and
depressed at the external side, and presents a much
less surface than the anterior. When the tooth
appears completely shot out, the inner surface
hardly rises above the gum, whilst in old horses it is
sometimes nearly as long as the outer surface. In
most teeth, particularly the corner teeth, it is divided
into two equal portions by a very remarkable groove,
that extends from the socket to the inner edge of
the tooth.
The extremity of the free portion of the tooth
{See plate l,fg. 2, 3, 4 5,) or that part by which
the corresponding teeth of each jaw come more or
less in contact, and by which they rub one against
the other, presents a broad surface flatted from front
to rear, that is denominated the table of the toothy
In teeth that have not been worn this table presents,
first a deep cavity stretching from one side to the
other, and which soon becomes filled with a yellow
and black substance; this has been usually termed
B 3
18
AGE OF THE HORSE.
the mark ; second two elevated edges that bound the
cavity, having an unequal height, and joining, form
an acute angle at each side. The outer or anterior
edge is longer and higher than the inner or posterior
edge, the latter presents a tolerably deep nick in the
centre formed by the continuation of the groove of
the posterior surface: consequently the surface of
wearing ought not to be called the tahle^ until after a
certain degree of wear, when the two edges are upon
a level. Then the cavity only forms part of the surface
of wear, in the centre of which it is seen formed by
a sort of funnel, which, according as the animal ad-
vances in age, becomes narrower, gets closer to the
posterior edge, and finally disappears entirely. The
body of the tooth, as well as this dental funnel or
infundibulum, undergoes similar changes, in truth
much more slowly, but which is notwithstanding
very perceptible, when the infundibulum presents
only a round, and is arrived at the full term of its
wear. It has like the infundibulum a conical shape,
and the narrowness that it presents next the gum, is
so remarkable in the incisors of the ox, as well as
in the old temporary incisors of the horse, that these
teeth appear as if coming to a shank next the edge
of the socket.
As to the lateral edges of the free or exposed por-
tion of the incisors, the inner or that which is
next the median line* is rounded, and much thicker
* Median line, is a term frequently occurring in French
anatomical works, by it is meant an imaginary line dividing
perpendicularly the body, head and neck into two equal
parts. Tratstsl.
AGE OF THE HORSE.
19
than the outer edge, which is generally thin, and
even sharp in the corner teeth. In the young sub-
ject these edges lap over, the outer projects forward
and is seen placed over the inner. This sort of lap-
ping over would seem to proceed from the manner
of the growth of the incisors, that always appear
by opposite pairs, which only get into line by de-
grees and at the end of a certain time, this lapping
over is perceptible until towards eight years of age.
The portion buried in the gum, generally called
the root of the tooth, is firmly implanted in the
maxillary socket ; it is curved backwards, forms a
well marked convexity anteriorly, and ends in a
blunt point. The nippers are parallel to the axis of
the jaw, or in other words perpendicular to it ; the
dividers are oblique, and the corner teeth still more so,
with their roots turning inwards. The arcade formed
by the roots of these teeth, is much narrower, and
takes up less space than that of the free portion.
The length, the shape, and the size of the root
varies according to the different degrees of age, and
presents some differences that it is necessary to
point out. During the period of the protrusion of the
tooth, the root is generally short, round, and quite
hollow ; its internal cavity, the sides of which are
very thin, is only of temporary duration, and does
not present, like the external cavity, a sort of fun-
nel or infundibulum, which is peculiar to the latter.
It buries itself deeply, is prolonged externally, sur-
rounds the outer funnel, and contains a pulpy sub-
stance, that seems to be the central germ of vitality
and nourishment of the tooth. According as the
20
AOS OF THE HORSE.
subject advances in age, this cavity at the root
diminishes progressively, and its obliteration pro-
ceeds from the bottom of it, beginning towards the
inner edge of the tooth, it is collected from the side
next the root. The latter lengthens, continues
constantly to grow, and the fresh portions, instead
of being rounded, are successively triangular, then
flatted from side to side ; and finally, at a period
that varies according to the teeth, the cavity disap-
pears altogether ; the root is then pointed at the
end, and entirely ceases to grow.
The entire length of the temporary incisors, is
from about fifteen to twenty lines, and of the horse
incisors, from two inches and a half to three and a
quarter. Their form as we have seen is not the
same throughout. Thus, next to the surface of wear?
flatted from front to rear, they narrow towards the
edge of the socket, and become in succession, first
oval, then rounded ; towards the base of the root
they are triangular, and their extremity flatted from
side to side. This difference is much more remark-
able in the nippers and dividers than in the corner
teeth, this is very easy to demonstrate, by making
several transverse sections at two lines apart of an
incisor tooth. (See 2^late 2, fig, 10.)
The arrangement of the two cavities is such,
ihat they cross each other in the interior of the
tooth ; the exterior proceeds towards the posterior,
and the interior more particularly towards the ante-
rior edge : they are separated by two divisions or
partitions that differ in their nature and density, to
which M. Girard, sen. has given the name of dental
AGE OF THE HORSE.
21
septa, and which remain jointly on the table of the
tooth up to a certain period of life. ( See plate 2,
fig. 3.)
The incisors vary amongst themselves in length,
shape, and the depth of their cavities. The corner
teeth are in general shorter than the dividers or nip-
pers, and have not so regular a form : they are nar-
rower towards the external lateral edge, so that they
never become as perfectly oval, rounded, or triangular
as the others ; the infundibulum is also less deeply
inserted into the interior of the tooth.
In general, we find the infundibulum, when the
incisors have completed their growth, from nearly
six to seven lines long in those of the lower jaw,
and nearly double that in those of the upper jaw.*
The incisors of the upper jaw are likewise stronger,
broader, and more developed than those of the lower.
Hence it happens that the outer edge of the lower
corner teeth rest against the centre of the upper
corners, and wears them in such a way as to produce,
in some jaws a triangular nick, which is to a certain
extent a guide in determining the age. This nick,
which never appears until seven years of age, disap-
pears in time, but more quickly in proportion as the
jaw takes a more horizontal direction.
The temporary incisors are in general broader than
* In the horse of six years old, the infundibulum of the
lower nippers is from six to seven lines, that of the dividers
from seven to eight, and the corners from five to six. In
the upper javi^ the length of the infundibulum of the nippers
is from eleven to twelve, the dividers from twelve to thirteen,
and the corners from eight to nine lines.
22
AGE OF THE HORSE.
those of the adult (in proportion to their length) and
are in the beginning of a greyish white; their exterior
surface is covered with a number of small shallow
striae, and the channel of the posterior surface is but
slightly marked. In a more advanced age, and as they
approach the period of their fall, the exterior surface
becomes bright and polished like those of the horse
teeth and the stiiee give place to small channels; but
then the teeth are separated from each other, and
present ^.t their base a narrowing into a regular neck,
that we never meet with in the horse teeth, be the
animal ever so old. {See plate 1, fig. 11, 12.)
AGE OF THE HORSE.
23
2nd. MOLAR OR GRINDING TEETH.
f Columelares Denies. J
The molar teeth, twenty-four in number, of which
twelve are in each jaw, six to the right and six to
the left, are placed firmly by the side of each other
in their sockets in the maxillary bone, and form the
lateral portions of the dental arcade. From the first
molar on each side to the tush, the distance is about
four inches, but the space is a little less in the lower
than the upper jaw.
The anterior molars, three in number on each
side, have long been (and upon the authority of
Aristotle) considered as permanent. BufFon, Bour-
gelat, Daubenton, &c. continued to look on them as
such, although Ruini had published, in 1598, that
two of these teeth were temporary ; and that error
was persisted in, until Tenon* had established posi-
tively, that the three anterior molars were liable to
fall and to be replaced.
Each molar considered in the adult, presents a
free or exposed portion and a concealed or implan-
ted portion ; the free portion protrudes beyond the
gum about five or six lines ; its external surface which
is nearly upright, presents in the teeth of the upper
jaw, two longitudinal grooves, nearly always how-
ever in the first horse molar there are three of them;
in the sixth lower molar these grooves are replaced
by two channels. In all the other lower molars there
is only one very deep channel, that extends down to
* Loco citato.
24 AGE OF THE HORSE.
where the root divides. The interior surface is not
so high as the external in the molars of the upper
jaw, but on the contrary is the highest in those of
the lower jaw. As to the lateral surfaces, they are
straight, and applied throughout their extent to the
corresponding surfaces of the neighbouring teeth.
The surface of wear in the unworn tooth is composed
of small bands, arranged in zig-zag, leaving inden-
tations between them, that are broader and deeper
in proportion to the youth of the tooth. The bands
that circumscribe these indentations are also sharper
when the tooth has not been worn, and this provision
undoubtedly assists the exit of these teeth from their
sockets. When the molars have been worn, they
present a different appearance ; the edge of the cir-
cumvolutions are blunt; the indentations appear
filled up and levelled ; finally the surface of wear
becomes changed into an uneven table of a regular
quadrilateral shape, taking a slightly oblique direc-
tion, from within outwards in the lower jaw, and
from without inwards in the upper jaw. The surface
of this table is then formed of transverse eminences
and depressions, disposed regularly in the direction
that the teeth rub on each other.
The embedded portion, or the root of the molars,
extends into the bottom of the socket, and present
a proportion and a length that varies in the different
teeth. The third and the fifth are gerxcrally longer
than the others, and according to Tenon, they con-
tinue the longest during life. They are stronger in
the upper than in the lower jaw, and they exhibit
through their whole extent, the continuation of the
AGE OP THE HORSE.
25
channels and grooves that we have remarked in the
free or exposed portion.
The root of the first molar is directed forward ;
those of the second and third are straight, the three
last point backwards ; their extremities are pierced
with many deep cavities that cross those of the ex-
terior, do not communicate with them, but like those
in the roots of the incisors, are deep in proportion
as the animal is young. Finally, at a certain period
(generally from four to five years old) the extremity
of the root throws off fangs to the number of three
in the first and sixth upper molar, and four in the
other molars of the same jaw.* In the lower jaw
the first and last are tricuspid, and the others are
bicuspid. Sometimes, however, the first only pre-
sents two fangs.
Besides these molars there are sometimes others,
that have been called supplementary. These latter
have some resemblance to the first molar of the dog,
are placed one on each side of each jaw, anterior to
the first temporary molar ; and as the first replacing
molar is larger than the temporary, it almost al-
ways happens, that in pushing out the latter it also
pushes out the supplementary tooth, so that it is
very rare to find one after two years and a half old ;
besides which they are not always present.
It is generally with the molars as with the incisors,
that those of the upper jaw are bigger, stronger,
and their dental arcade broader, than those of the
* We sometimes, though very rarely, find a supplemen-
tary hinder molar situate close to the sixth.
c
26
AGE OF THE HORSE.
lower. Their arrangement with respect to the in-
cisors is such, that when the molars are in contact
the incisors are separated, and vice versa; this was
necessary, on account of the incisors acting from
front to rear, and the molars from side to side,
OP THE TUSHES.
f Denies Canini.J
The Tushes or Tusks, so called more on account of
their form in the hog and wild boar than that which
they present in the horse, are situate in the interval
that separates the incisors from the molars and much
nearer the corner teeth in the lower than in the
upper jaw, where they are nearly an inch and a half
distant from them. It follows from this arrange-
ment, which is similar to that which exists in carni-
vorous animals, that tushes do not rub against each
other, but cross when the jaws close.
The free portion of these teeth represent a come
with its base next the socket ; its external surface is
convex and striated, its internal surface presents in
its middle a conical eminence, circumscribed by two
very deep grooves, that unite at the point and are
separated at the base.
The embedded portion, which takes a direction
backwards like the corner incisors, presents at its
extremity the orifice of a cavity that in young teetU
is prolonged up to the extremity of the free portion;
according as the animal advances in age, this cavity
becomes obliterated, commencing at its bottom; the
AGE OF THE HOUSE.
2-7
root diminishes in thickness and increases in length,
like a tube of glass drawn out over a lamp; finally
the cavity disappears altogether.
The tushes differ but little from each other ; those
of the lower jaw however are a little longer and
stronger. They seem to belong exclusively to horses ;
mares are not provided with them, or at most
they have only the rudiments of them, resembling
supplementary molars ; it happens very rarely that
they attain any considerable size, but still it is pos-
sible to be mistaken on this point; when they do,
they are small teeth having no eminence or grooves
on the inner surface.* Castration does not produce
any effect on the size or strength of the tushes, or
on the period of their appearance, which is ex-
tremely variable, and without any cause that we are
acquainted with.
* The ancients supposed that mares having tushes were
barren, and called them brehaignes. (I have never heard &
word in English to express this epithet. Transl.)
28
AOE OF THE HORSE.
ARTICLE II.
ORGANIZATION OF THE TEBTH,
The teeth are composed of two substances, dif-
fering in their color, their density, and their uses :
the one which is exterior is called enamel; the other,
interior, is called vulgarly the bony substance ; but
which is with much more propriety called by Hunter
and M. Cuvier the ivory. This substance is not in
fact bone: it is not produced, it is not supported,
and it is not re-produced, after the manner of the
bones : it has no analogy with them except in its
chemical composition ; but even in this, according
to M. Morichini and M. Berzelius, there is some
difference, for they have shown the presence of a
small quantity of fluate of lime in it.*
The ivory exists throughout the whole substance
of the tooth ; towards the free portion it is covered
by enamel, and only forms the root to it It is of
a yellowish white, very compact, and formed of
striae ranged transversely to the axis of the tooth,
which gives it a silky appearance.
The finest injections have not demonstrated any
vessels in it; but we must admit, however, that
soaking causes liquids to penetrate into its deepest
layers, in the same manner as they penetrate into
horn, which is always softer at its internal surface,
as is well known. The red color that the internal
layers of the ivory of the teeth assume in those
* The general opinion of chemists is, that we do not find
fluate of lime except in fossil bones and teeth.
A(il OF TK12 HORSE.
29
animals that are fed with madder, at least while the
teeth are growing, is alone sufficient to prove that
this absorption takes place. The recent observa-
tions of MM. Magendie and Fodera tend to demon-
strate, that the mechanism of absorption is itself
under all circumstances nothing but an imbibition.
The ivory of the young incisors is prolonged
down to the extremity of the root ; on the contrary
it becomes more distant from it in proportion as the
root increases in length, and the tooth is pushed out
of the socket. The enamel forms a sort of crust
over the eburnous^ substance of the free portion ; it
is of a milky white, and is more polished in the
adult teeth than in those of the young or of old
subjects : its hardness is such, that it gives fire with
fiifit: it is completely impervious to injections. Its
chemical composition is a little different from that
of the eburnous substance ; it is almost entirely
formed of the phosphate of lime, and contains a
small quantity of animal matter, which amounts,
according to Berzelius, to but two per cent, whilst
there exists in the bony substance of the tooth from
twenty-eight to thirty per cent.
The interior of the teeth is provided with a cavity
that communicates with the bottom of the socket,^
by means of an opening in the extremity of the
root, the diameter of which is greater in proportion
as the tooth is young. This cavity diminishes with,
age: it is filled with a gelatinous, greyish substance,
which is simply a papilla filled with mucus of the
* From ebur, ivory. Transl.
c 3
30
AGE OF THE HORSE.
mouth, surrounded by a membrane abounding in
vessels and nerves, which do not penetrate into the
eburnous substance.
The arrangement of the ivory and the enamel
varies in each kind of teeth ; it is not the same in
the molars as in the tushes, nor in those as in the
incisors ; v^^e shall only examine it in the latter, as
they are the principal object for our consideration.
The enamel, after having covered the entire of
the external surface, doubles itself towards the sur-
face of wear, and dips down into the interior of the
tooth, forming a conical cavity, which becomes
narrow, and approaches towards the posterior edge
of the tooth, the more according as it is nearer the
root. This prolongation of the enamel presents
then two portions for our consideration : — first, the
cavity that it forms to the exterior: — secondly, the
horn or infundibulum which envelopes this cavity.
This funnel, which is very easy to perceive in mak-
ing different sections of the tooth, is surrounded in
young teeth by the cavity of the pulp, which is con-
tinued to the extremity of the free portion, hut
which is found more especially on the side corres-
ponding to the anterior edge of the tooth. As the
animal advances in age this outer cavity becomes
obliterated, and the infundibulum is then only sur-
rounded by a mass of ivory, much thicker anteriorly
than posteriorly. {See plate 1, fig. 7, 8, 9 ^' 10.)
Veterinary anatomists admit yet a third substance,
which they call the cortical substance, or the ce-
ment, and which, according to them, covers the
exterior surface of teeth that have not undergone
AGE OF THE HORSE.
31
any wear. That v/hich they consider as a peculiar
substance, is evidently a portion of greyish or yel-
lowish enamel, which has .not as yet acquired the
hardness and color that it afterwards possesses.* They
TdLTi^e in the same class the matter that fills the bot-
tom of the inner cavity or infundibulum and forms
t/ie mark. In the very young tooth this cavity ex-
tends to the end of the funnel, and terminates in a
cul-de-sac^ or blind pouch. Subsequently, when
the tooth is a little worn, it wants from three to four
and even five lines of being so deep, which is filled
up by a yellowish substance, that is nothing more
than tartar, to which it has the most perfect analogy
both as to its physical and chemical characters.
As has been already remarked, the teeth are
formed in the interior of the maxillary bones ; but
their developement occurs sooner or later in differ-
ent animals. In the foetus of a mare three months
gone, there are not as yet any traces of teeth. We
can merely perceive cavities in the interior of the
jaws, that are subsequently to be converted into
sockets ; they contain vesicles that are the future
nuclei of the teeth. Towards the fourth or fifth
month these vesicles exhibit at their summit, next
the side of the socket, one or more plates of ossific
substance, which are not long before they unite, and
form those circumvolutions that are subsequently
* This substance has lately been submitted to analysis.
It is composed, according to M. Tassaigne, of 53,9 of phos-
phate of lime, 3.9 of carbonate of lime, and 42.2 of a
parenchymatous animal matter, analogous to that which exists
between the teeth and the bones.
32
AGE OF THE HORSE.
perceived on the table of tbxe tooth. These plates
increase quickly in thickness by the addition of new
layers to the internal surface,* It at the same time
becomes more developed on the sides, always, how-
ever, tov/ards the extremity that is intended to pro-
trude outside beyond the gum, so that the root may
be the last formed, and that the plates of ivory may
always be thicker towards the summit of this dental
nucleus. It follows from this that the pulp decreases
in proportion as the tooth becomes larger ; and that
this process, or this ossification, (if we may be al-
lowed the expression,) continuing throughout the
duration of life, a period should arrive, and which,
in fact, is the case, wherein the pulp has entirely
disappeared, and wherein there does not any longer
remain a trace of the cavity in which it was con-
tained.
The enamel is not formed in this manner by the
addition of successive layers from within outwards ;
it is secreted by the membrane that lines the sides
of the socket, and spreads itself over the ivory which
it encloses down to the extremity of the root. Its
thickness remains always the same. The enamel
once formed, it does not undergo any further
change. In the young molars, we very distinctly
perceive this substance applied against the ivory in
the form of plates running parallel between them,
and also to the axis of the tooth : these plates have
a certain analogy in their appearance to the leaves
* This opinion is not exactly in unison with that of M. da
Biainville. Vide Diet. d'Hiat. Natur. art. Dent.
AGE OP THE HORSE.
33
of the reticular tissue of the anterior surface of the
foot of the horse ; they do not acquire all their
density until a later period, and but a short time
before their protrusion, but always proceeding from
the edge of the tooth next the socket. The enamel
does not receive any more vessels than the eburnous
substance, though in all other respects it differs
essentially from it. It does not increase in thick-
ness with age ; it does not become red under the use
of madder j when it is broken, the fragments do
not again unite as those of the ivory do, by the ad-
dition of new layers ; it does not contain fluate of
lime ; finally it dissolves more or less completely in
a dilute acid, whilst the ivory preserves its form,
and merely becomes transparent and flexible.
The formation of the dental vesicles and their
ossification does not take place precisely at the same
period in all animals.
In the foetus of a mare four or five months gone
we find twelve opaque dental vesicles that are begin-
ning to ossify, that is, six for the molars and six for
the incisors (the corner teeth are not hardly percep-
tible.) According as the fostus approaches towards
the full period of its sojourn in the womb, the ossi-
fication increases, so that towards the ninth month
the teeth have already become very solid, even the
corner teeth themselves are ossified, and we can
perceive sufficiently distinct the vesicles of all the
teeth that in course of time will protrude.
As the tooth continues constantly to grow, and
that too in every direction, it gradually separates
the sides of the cavity that contains it, and which in
34
AGE OF THE HORSE.
a short time ceases to be sufficiently large to contain
it; it must then endeavour to perforate the socket
on tiiat side that presents the least resistance, and
consequently it protrudes on the side next the mouth
towards the alveolar edge of the maxillary bone,
penetrating the bone and the gum covering it.
When the teeth have once accomplished their
protrusion, they continue to grow in length in their
roots, or in other words to shoot their roots deeper,
during a much longer time in the horse, and other
monodactyls,* than in the other large herbivorous
domestic animals. This continual growth being
accompanied with an equal tendency to push out-
ward, it follows of necessity that the portions worn
away are constantly replaced by others, and that
such portion of the tooth that at six years old formed
part of the root, at a more advanced period of life
forms the table. It is according to this continual
growth of the incisors, that Tenon, Lafosse, Pessina^
and M. Girard, sen. have established principles, by
which it is possible to point out the age of horses
that have passed seven or eight years, with more
certainty, than by means of characteristics given by
Butfon, Daubenton, Bourgelat, &c.
In fact, we have seen that an incisor that hss
completed its protrusion, but which has not as yet
undergone wear, is flatted from front to rear towards
the extremity of the free portion or table ; ihat at
some lines lower down it is oval, then rounded, then
triangular, and finally flatted from side to side. As
* From monos, ^in^le, and dactulos, Gr. a finger. Tnxyst,
AGE OF THE HORSE.
3a
the tooth pushes out in the same proportion as it
wears, each of these oval, rounded, triangular por-
tions, &c. become in succession the table of the tooth,
and form the surface of wear: it is sufficient then
to specify at what periods these changes take place
in the table of the teeth to form sufficiently correct
ideas on the age of old horses. It is the same with
the cavity or infundibulum : it contracts, becomes
oval, triangular ; and when it has disappeared
gives place to the cul-de-sac, or blind pouch, of the
root. . The period of the disappearance of the in-
fundibulum has also been observed by M. Girard,
sen.; he has also noted the appearance of the end
of the cavity or funnel that contained the pulp, and
to which he has given the name of the internal den-
tal septum. {See plate 2, Jig. 3, 5 ^ 6,)
It is not alone in consequence of their dispropor-*
tion to the alveoli or sockets, that the teeth are pushed
outwards. At the period when the cavity is obliter-
ated, and when the roots have ceased to increase in
length, the maxillary bone itself becomes increased,
pushes them outwards, and ends in part by filling
up and obliterating the alveolar cavity.
This action of the jaws on the teeth is not matter
of doubt. The shape that the head and the teeth
assume in old age proves it. We have stated that
the incisors, which are very broad towards their
wearing surface, were much narrower towards the
socket. This last portion, at a more advanced age,
forms the surface of wear, and the tooth is then
nearly the same breadth throughout. The incisors,
should then be, as in the ruminating animals, sepa-
36
AGE OF THE HORSE
rated from each other; on the contrary they are in
contact, and this phenomenon can be perhaps only
the result of the action of the maxillary bones.
It would be difficult to determine in what pro-
portion an incisor tooth protrudes in the year.
However, Pessina has attempted it: he affirms,
that in high-bred horses they are worn a line a year,
and a line and a half in common horses. As their
length is always nearly the same, at least in the
greater number of horses, it will follow from that,
that these teeth are pushed outwards in the same
number of lines each year.
When a molar tooth is wanting, the tooth cor-
responding to it in the other jaw acquires a consi-
derable length : it is not then the wear that causes
the continual protrusion of the tooth ; the growth
continues nevertheless. Examples of this sort are
frequent.*
All that we have just said applies particularly to
the adult teeth, to those that have taken the place
of the foetal teeth, and that remain during the rest
of life.
Otherwise these teeth follow in their evolution
the same order as the sucking teeth : every thing
♦ Tenon has calculated that the molar teeth of the horse
ar^ capable of acquiring a length of about six inches, in case
they lost nothing by wear. In the head of a mare killed for
dissection in October 1805, marking from six to seven years
of age, one of the upper right molar teeth that had not been
worn but at its inner surface, presented from the cxtreniity
of the root to the extremity of <he free or exposed portion,
a length of about tive inches, and this diminution is pretty
mach the same in the five other molars.
AGE OF THE HORSE.
37
leads us to believe that they exist at the same time
with them, and that they only require a longer time
to arrive at perfection. They form a range of vesi-
cles within or behind, and above or below the tem-
porary teeth, and present precisely the same consi-
derations. In the beginning they exist at the bottom
of the socket, approach by little and little towards
the alveolar edge, become ossified, destroy the par-
tition that separates their cell from that of the
temporary tooth that corresponds with them^ de-
stroy the root of the latter, compress the vessels
and nerves that go to it ; finally they determine their
fall, and are not long themselves in making their
appearance.
There is not only wear, but also absorption of the
root of the temporary teeth. This is particularly
remarkable in the molars, and which form only a
small plate when they fall.
The replacing molars pushing immediately down
on, or up against the temporary teeth, it is easy to
account for the fall of the latter. In the incisors it
is not the same ; the replacing teeth form a broader
range than the temporary teeth, and situated behind
them in such a way, as that their extremities do not
exactly correspond. Whence it follows, that the
replacement of the incisors takes place generally
much less regularly than that of the molars, and
that they present supernumerary teeth frequently.
The manner of the growth and protrusion of the
replacing incisors, also explains why the roots of the
temporary teeth become depressed at their anterior
surface, and at a certain period only form a long,
D
38
AGE OF THE HORSE.
thin process, liable to break more or less near the
neck of the tooth, and to remain fixed in the
socket against the replacing tooth. These portions
of teeth are observed more particularly when the
sucking teeth have been drawn too early, and the
root broken. The destruction of this root by the
replacers, causes the table of the latter never to
exhibit the radical covering, and the reason of this
is so evident as not to need explanation. We shall
also point out that, when the temporary incisor
ceases to receive nourishment, it becomes whiter,
more smooth, and polished.
/
AGE OF THE HORSE.
39
. ARTICLE III.
SIGNS BY MEANS OF WHICH WB CAN DISTINGUISH
THE AGE.
The teeth are incontestably the parts of the body
capable of furnishing the most certain indications of
the number of years that the animal has lived, and
the incisors in particular are suitable for this purpose ;
they are indeed the only teeth that give correct ideas
on the age of the horse, throughout almost the
entire duration of his life. The difficulty of exami-
ning the molars, and the irregularity of their table,
prevent our being able to obtain any result from the
inspection of these teeth. As to the tushes, besides
mares not being provided with them, the period of
their protrusion varies very much : as they do not
rub against each other but sideways and across, they
can only be considered accessory means of judging.
The study of the age of the monodactyls, by an
examination of the incisor teeth, presents three dis-
tinct periods, the changes peculiar to the temporary
teeth, the protrusion, and obliteration of the mark
in the replacers, and, finally, the different shades that
these latter present, beginning at the obliteration of
the mark, and going down to the most advanced old
age.
40
AGE OF THE HORSE
1st. THE PROTRUSION AND OBLITERATION OF THE
MARK IN THE TEMPORARY TEETH.
Foals that have arrived regularly at the full term,
are generally foaled in the spring of the year, and
it is also from this season that horses' ages are reck-
oned from in each year. It is very rare that at this
period any of the incisor teeth have made their
appearance; the first and second molars are the only
ones that have shot out; when they are not at the
time of birth, they never delay more than three or
four days; the third is always shot out before a
month,
The nippers appear from six to eight days,
The dividers from thirty to forty days,
The corners from six to ten months.
We perceive, at the time that each incisor makes
its protrusion, a sharp edge convex anteriorly and
concave posteriorly, this is the anterior edge, the
posterior does not appear for some days after, and
it is then we distinguish the cavity.
The protrusion of these teeth takes place earlier in
proportion as the mother is in good health, the foal
well fed and in good health itself. As to the rest,
a precise knowledge of the moment of the appearance
of the temporary incisors is of little importance at
this period, when the foal has not as yet quitted the
mother, or at least not far separated from her, so
that positive information of his age can be obtained.
( See plate 1st, fig. I, J
The incisors of the upper jaw generally appear a
little earlier. This however is not so far general that
the contrary does not occasionally happen.
AGE OF THE HORSfi.
41
The two molars that appear at birth, still mark
the age of two to two and a half years by their fall,
and the protrusion of the replacers; but from this
period the molars can assist in a knowledge of the
age, and we should only consult the incisors.*
From the moment that incisor teeth have appear-
ed, they undergo some change in consequence of
their wear against those corresponding and opposed
to them. The wear commences on their anterior
edge, it being much more elevated and sharpen In
a short time it is on a level with the posterior ; then
they both wear together; the cavity which was at
one time longways, becomes narrower, and after-
wards triangular; finally, at a certain period it dis-
appears, and is replaced by the small end of the funnel
next the root; it is this wear taking place regu-
larly that is called Hosing the mark, ( See plate \8t,
jig, 4.J This wear takes place from the moment
that the upper and lower teeth come in contact,
whence it follows that obliteration of the mark is
often completed in the nippers when the corner teeth
are beginning to appear : as to the rest, it is very
variable in the sucking teeth, and can only give indi-
cations not much to be depended on, either because
there is great irregularity in the period of the appear-
ance of the corner teeth, or on account of variations
* The supplementary molars, when they are present, ge-
nerally appear from five to six months old.
As to the hinder molars, it is too difficult to examine them
for them to be of any service to a knowledge of the age.
The first appears about ten or eleven months, the second
about twenty months, and the third from four to six years.
D 3
42
AGE OF THE HORSE.
in the period of weaning the foal ; and also if they
have made use of fibrous food ; or else because the
food varies much in hardness in different situations.
When an incisor tooth has commenced wearing,
and that its two edges are on a level, the table pre-
sents two bands of enamel, the one exterior, that
surrounds the tooth, which is the casing enamel;
the other internal, that only surrounds the cavity,
which is the central enamel,"^ {See plate 1st, Jig. 3, 4.)
In every case, the incisor teeth of the lower jaw
wear more quickly than those of the upper, and
their wear is also always much more regular. The
reason of this has been sought for without being able
to find one altogether correct: according to some
the rubbing body always wears more than the body
rubbed, and the lower jaw being the most moveable,
its teeth ought to be worn soonest; others have
thought that it was on account of the strength and
compactness of the upper incisor teeth, as in them
the exterior layer of enamel and the infundibulum
are thicker. The only cause of this difference lies
in the disproportion that exists between the infundi-
bulum of the superior incisor teeth and the infundi-
bulum of the inferior. In all the teeth that I have
examined and compared together, the cavities were
deeper and the infundibulum longer by about a third
in the upper teeth ; and that very well explains why
the upper teeth seem to wear more slowly, notwith-
standing that they wear quite as much as the lower.
Whatever may be the cause of this difference, it is
* Tenon, already quoted.
AGE OF THE HORSE.
43
very remarkable. We also observe that the wear
is much more regular in the lower jaw; that undoubt-
edly arises also from the manner in which it rubs
against the upper.
It follows, in all cases, from this observation,
which is particularly applicable to the horse teeth,
that it is difficult to determine the period of the
obliteration of the mark in those of the upper jaw,
and that all authors who have considered it as being
able to assist in the knowledge of the age, have fallen
into error.
The marks in the lower nippers are always obli-
terated at ten months,
The dividers at one year,
And the corners from fifteen to twenty-four
months.
The upper nippers have their marks already
nearly altogether obliterated, so that at two years
old the cavities have disappeared in all the teeth, as
well of the lower as of the upper jaw.
At this period the crowns of the nippers become
insensibly smaller, and they have become necked at
their base, they become dried up and put on a yel-
lowish brown colour; shortly after they loosen, have
hardly a hold in the gums, and fall to make way
for the other teeth. It is then that the second
period of the age of the horse commences.
2nd. APPEARANCE AND OBLITERATION OF THE MARK
IN THE REPLACING OR HORSE TEETH.
As we have seen, the replacing or horse incisor
teeth are ranged behind the sucking teeth, and
44
AGE OF THE HORSE.
appear successively like the latter, first presenting
the anterior, the appearance is followed in one or
two months after, by that of the posterior edge.
The teeth of the upper jaw also appear in general
from eight days to a fortnight sooner.
The nippers appear at from two years and two
years and a half to three years,
The dividers, from three years and a half to four
years.
The corners, from four years and a half to five
years ;
So that a horse of three years old ought to have
four horse incisor teeth, a horse of four years old
has eight of them, and at five years old all the inci-
sor teeth have appeared.
Such is the course pointed out in all works, but
without any explanation ; and this brevity has given
rise to more than one error. It is certain that if
Nature was left to herself, it would be almost always
thus; I say almost always^ because there are cases
where the state of the jaw is different.
We have already stated that we consider all
horses foaled in spring, but the birth may take place
(taking one with another) three or four months
sooner or later. In the case where it is late I should
suppose the individual to be of a breed that is slowly
developed, of weak temperament, and that it has
been badly kept; the other, on the contrary, is
placed under circumstances the very reverse. If we
examine them in the month of August; in one the
corner teeth have appeared, in the other there is no
appearance of them, the dividers alone being out.
AGE OF THE HORSE.
45
However both the one and the other are in truth but
four years old. Let us look at them nine months
later, in the month of May : the first has twelve teeth
well shot out; the corners in the second are only
beginning to appear, notwithstanding they are both
five years old.
It is always sufficiently rare for this to occur when
Nature is left to herself. But the dealers who are
interested in giving young horses the greatest age
they can, draw sucking corner teeth and sometimes
the dividers, and by this means hasten the appear-
ance of the horse teeth, giving the horse the appear-
ance of being older than he really is. It follows
from this, that every horse (particularly if the other
parts are well pi-onounced) that in the month of
May, and more certainly if in the month of June,
has not the corner teeth appearing, and even well
shot out, ought to be considered being but four years
old. In a word, a horse must have lived sixty
months to be five years old.* When the horse is
not quite five years, but wants only two, three or
four months of it, it is said Tie is rising five years
old. If he is on the contrary nearer to four than
five it is said he is four years old off. The difference
then between rising and off relates to the period of
* This is not meant as an attempt at wit. All veterina-
rians well know that, according to dealers, the corner teeth
are the teeth of five years old ; but, say they, a horse that
has his five-year-old teeth must be five years old. The
orders relating to the remounts (in the French service ) direct
that horses to be eligible should be five years, or sixty months
off.
46
AGE OF THE HORSE.
the year in which the examination takes place, since
they are all supposed to be foaled in spring.*
The first horse molar ordinarily appears from the
thirtieth to the thirty-second month; the two others
remain sometimes up to three years. The supple-
mentary molars, when they exist, are generally
pushed out by the first horse molar, at the same time
as th^ first sucking molar. Sometimes the latter
pushes out by the side of it, then the supplementary
molar remains a longer time; this happens more
frequently in the lower jaw, where the supplemen-
tary molar is not so near the first front molar.
It is at this period that the tushes appear. Their
time of appearance is by no means regular ; some-
times they appear at three years old, at other times
they do not until six ; but the more general period
* The appearance of the teeth, whether sucking or horse
teeth, does not take place at the same period in all coun-
tries. Thus, in the horses of the South of France, that are
reared in the district where they have been foaled, the horue
incisors make their appearance sometimes in the first days of
September, more frequently in the beginning of October;
but they are always shot out in the first fortnight of Decem-
ber. This protrusion is much later in the colder climates ; in
Normandy, for example, it does not take place, when Na-
ture is left to herself, but in the months of January, Febru-
ary, March, and even April. In Limousin is rarely finished
before the month of January. These variations depend so
much on climate, that when foals are transplanted from a
cold into a warm country, the appearance of the tei-th takes
place earlier ; it is more slow in the opposite case, and that
in proportion as the difference of the temperature is greater
between the two places.
AGE OF THE HORSE.
47
is four years old.* We cannot draw any but very
uncertain principles from the state of these teeth.
The exertion that the teeth make for their protru-
sion is in every direction, and not alone on the side
where they make their appearance ; it is easy to be
satisfied of this on the heads of horses or foals that
die during dentition. The plates of the maxillary
bones are worn, and often even perforated ; also
these periods, particularly that of the second denti-
tion, are those, in all animals, in which inflammatory
diseases make their appearance, differing in the dif-
ferent species, and more or less severe in proportion
to the difficulty with which the protrusion is per-
formed. The separation of the sides of the maxillary
bones, and the swelling that is the consequence of
it, gives to the head a roundness and an air of youth
that disappears with what gave rise to it.f
* I had in my own possession some years back, a good-
shaped, powerful chesnut gelding, able to carry fourteen
stone hunting, and of an excellent constitution, whose
age I knew without reference to his teeth to be seven off,
that had not the slightest appearance of tush ; his other teeth
exhibited the usual appearances at that age. Transl.
f From this circumstance, I some years since pointed
out to Mr. William Sewel, who then said it was quite new to
him, that we could make a pretty close guess at the age of
a horse in the dark, by taking the edge of the lower jaw
between the fingers, opposite the roots of the grinding teeth,
and laying the other hand along the side of the face opposite
the roots of the grinding teeth of the upper jaw, and if the
horse was young, the lower jaw would feel thick ar\d plump,
and the side of the face round and full ; but if old, the
lower jaw would feel quite thin, the roots of the grinding
48
AGE OF THE HORSE.
The obliteration of the mark in the horse incisor
teeth takes place tolerably regular ; but not so much
so as to enable us to distinguish precisely the age of
a horse, as one would be tempted to believe, in
reading all the veterinary works that have treated
on this subject.
They all say that the marks in the lower nippers
are obliterated at from five to six years old, and the
corners from seven to eight, &c. But from the age
of three years, the period when the nippers appear,
up to five, they have had time to wear, and they are
already almost quite smooth, when we perceive the
corner teeth ; it then follows, that it is to those
teeth that have undergone the least wear that we
should refer. Consequently, at this period we
should consult the state of the corner teeth ; and it
will be difficult to mistake in the exact age of the
animal, let us have had ever so little experience.
At five years old, when the circumstances that
we have pointed out do not exist, the corners coming
teeth having quitted it, the two plates of the jaw-bona come
in contact, and the side of the face will feel hollow, it
having fallen in from the same cause. Mr. S. has since,
however, I believe, attached much importance to this fact,
and I dare say has altogether forgotten where he got it. The
truth however is, it can only be of use in case a person
wished to steal a horse in the dark, which is an expedient I
trust none of my readers will have recourse to. I was also
the first who pointed out to him the existence of the subsca-
pulo-hyoideus muscle in the horse, of the existence of which,
although a highly important muscle, he was not before
aware. I also pointed out to him the utility of combining
aromatics with mineral tonics — cum multis aliis. Tramsl.
AGE OF THE HORSE.
49
to shoot out are not on a level with the dividers ;*
the anterior edge is much more elevated than the
posterior, and the anterior edge pf the dividers is
slightly worn ; in the nippers it is on a level with
the posterior edge, the cavity or mark has altogether
disappeared, or nearly so. The entire of the inci-
sor teeth wholly taken, as well superior as inferior,
represents a pretty regular semi-circle ; the tushes ^
are most generally completely shot out, but do not
as yet show any wear.
At six years old, the corners become a little
more elevated, and are found to be nearly on a level
with the dividers ; the outer edge is a little more
worn, the dividers are in the state in which the
nippers were at five years old ; the mark in the nip-
pers is always and completely effaced.^
At seven years old, the mark in the dividers is
obliterated ; the outer edge of the corner teeth is
on a level with the inner ; we sometimes perceive
a notch in the upper corner teeth.
Finally, at eight years old, all the lower jaw has
the marks obliterated in it :t the teeth are on a
* We speak constantly of the lower teeth when we do not
distinguish them, as they alone have the mark obliterated
with regularity.
+ At this period the last molar tooth has shot out, and the
horse has forty teeth, of which twelve are incisor teeth,
twenty-four molar teeth, and four tushes, without counting
the supplementary molar teeth when they exist.
:}: These, however, are not always so. The cavity Qr
mark in th > corner teeth often remains at nine years old,
and even beyond it. This arises from these teeth not wear-
ing regularly.
E
50
AGE OF THE HORSE.
level, their form is changed, they have become oval,
and the cavity has been replaced by a longish trans-
verse eminence of enamel, which is the termination
of the central enamel or the funnel next the root. —
{See plate 1, fig. 10.)
3rd. THE SUCCESSIVE SHAPES THAT THE TEETH
ASSUME, AND THE DIMINUTION AND DISAP-
PEARANCE OF THE CENTRAL ENAMEL.
After eight years, the obliteration of the mark
in the superior incisors is, according to the greater
number of authors, the only means of ascertaining
the age of the horse. For a great length of time
we have perceived the insufficiency of this method,
since people are in the habit of declaring all horses
aged that have passed eight years old. This expres-
sion has been a kind of anathema to all those that
it has been applied to. But there is nevertheless a
great difference in value and capability of perform-
ing service between a horse of nine years old and
one of eighteen ; and it certainly is not a matter of
indifference to be able to distinguish the ages of
those that have passed this terrible epoch.
We have already seen that the incisors, as well as
the other teeth of the horse, are continually growing
during life, and that every part of them in succession
forms the table, and that when the wear had been
regular, when in a word they had been fairly worn,
this table becomes by age oval, rounded, triangular,
and finally flattened from one side to the other.
( See plate 2, fig. 9, J We shall extract from the
AGE OF THE HORSE. 51'
observations of Pessina, which by the way are in
every respect too minute and too circumstantial,
those of the correctness of which experience has
convinced us, and which we consider ought to be
admitted.
The incisors that at the period of their appearance,
and at three, four, and five years old, were flattened
from front to rear, and very long from side to side,
diminish progressively in extent in this latter dimen-
sion, so that at eight years old the nippers of the
lower jaw have taken on an oval shape, and we
remark that the dividers and the corner teeth do the
same in succession, and become narrow by little and
little ; the tables of these same teeth become round
up to thirteen years of age, they then put on a new
appearance, and become triangular in the same order
in which they had become oval and rounded. ( See
plate 2, Jig. 7 J
This triangular form is not very much pronoun-
ced in the beginning, the edges are slightly rounded,
and the three sides are pretty much of an equal length,
afterwards the lateral portions grow longer, whilst
the anterior or outer side appears to diminish; the
extremities become angular, and this lengthening in
a short time becomes so great, that at from nineteen
to twenty years of age, the incisors become in real-
ity flattened from one side to the other.* Cfiff' 9. J
This flattening proceeds in succession from the nip-
pers to the dividers, and from them to the corner
* This tlattenitig- from side to side (the biangularity of
Pessina) is not well pronounced in some horses, it is in ge-
neral a very long, or in other words, a very acute triangle.
E 2
52
AGE OF THE HORSE.
teeth, in such a way as to enable us to distinguish
the age of the horse up to twenty -two or twenty-three
years.
Such is the substance of Pessina's remarks, and taken
thus in the general way, they are sufficiently correct.
We cannot, however, say the same of the details
that he gives, nor of the divisions and sub-divisions
that he establishes between those different periods.
But further he reasons as if the rounded, triangular,
and biangular shapes, were as regular as geometrical
figures ; but undoubtedly this is very far from being
the case, at least in the greater number of instances.
One would believe, according to what he says, that
the teeth of the upper jaw wear with as much regu-
larity as those of the lower, and that the characters
they present, and the principles we can deduce from
them, are equally regular and equally invariable.
To demonstrate the error into which he has fallen,
we can only repeat what we have already said on the
obliteration of the mark or disappearance of the ex-
terior cavity in the teeth of either jaw. In fact,
if we believe what he says on the subject, he has
arrived at the highest degree of correctitude in the
knowledge of the age of the horse, and that the ap-
pearance of these different shapes is so regular, so
exact, and so well marked, that it is not possible to
be deceived even to a few months. We leave the
correctness of these assertions to the judgment of
Veterinarians.
When in consequence of the obliteration of the
mark the external cavity has disappeared, we no
longer perceive on the wearing surface any thing
AGE OF THE HORSE.
53
but a grain of enamelly substance, longish from one
side to the other, and having a slight depression in
its centre,* and it is placed a little nearer to the
posterior than to the anterior edge of the tooth.
This grain, which is merely the termination of the
fiinnel next the root or central enamel, still remains
up to a certain period, becomes narrower, rounded,
approaches closer to the posterior edge of the tooth,
and finishes by disappearing entirely. C See plate 2,
fig. 5. J These successive changes, and this disap-
pearance, will cease to astonish us when we recollect
the situation of the funnel next the root, such as we
have already described it. We at the same time
said, that this pulpy cavity was prolonged into that
portion of the tooth which is outside the gum betv^^een
the two internal surfaces of the central enamel. This
cavity becoming obliterated by the addition of new
layers of ivory, exhibits in the course of time, like
the exterior, an infundibulum of ivory substance,
which in consequence of the continual growth and
wear of the tooth, appears at a certain period on the
wearing surface.
" Before the complete destruction of the first of
" these marks (the central enamel) when it is nearly
" oval, we perceive the termination of the pulpy
" cavity appear in front of the first, and against the
• The prominence of the central enamel is caused by its
bein^ surrounded with ivory, which being much softer, wears
more quickly. This inequality is particularly remarkable
in the table of the molar teeth, where we can extremely well
distinguish the bands of enamel, which gives them some ap-^ "
pearance of a worn mill-stone.
E 3
54
AGE OF THE HORSE.
anterior edge of the table, in the form of a zone,
afterwards transverse and yellowish, then round
and greyish, and after that white and longish from
" front to rear. It differs essentially from the first
" mark in its never becoming prominent, and its
being always on a level with the remainder of the
"surface of the table: we also observe that it con-
" tinues until the fall of the tooth; and that if it
" sometimes disappears, it is invariably replaced by
" a small round black cavity."*
We should recollect, before going further, that the
funnel of enamel which envelopes the external cavity
is not of the same length in all the incisor teeth ; it
is generally longer in the dividers than in the nip-
pers, and in the latter than in the corner teeth, and
this difference is sometimes so great that it has dis-
appeared in the latter teeth when it still remains in
the others. We already know that its length is
comparatively greater by nearly one half in the
upper incisor teeth ; the central enamel ought then
to remain much longer in them. However, the total
length of the upper incisor teeth is the same as that
of the lower; they ought all then to undergo their
change of form in the same time, since they are
of the same length, as they wear, and grow out of
the gum continually, and the same number of lines;
and the observations of Pessina on this point are
altogether incorrect.
We are reasoning in the supposition that the wear
in the teeth of the upper jaw takes place regularly ;
* Letter from M. Girard to M. Teissier, already quoted.
AGE OF THE HORSE.
55
but we have seen that most generally such is not the
case.
} In applying the principles that we have been just
explaining, we may distinguish the age at different
periods, according to the following characters.
At eight years old C See plate 2, fig. I. J complete
obliteration of the mark (most generally) in the
lower jaw, the nippers, the dividers, and the
corner teeth, the central enamel is triangular and
nearer the posterior than the anterior edge of the
tooth, the termination of the cavity next the root
appears near the anterior edge in the form, of a yel-
lowish band, longish from one side to the other.*
At nine years old CfiO- 2« J the nippers become
rounded, the dividers oval, and the corner teeth
have become narrow, the central enamel diminishes
and approaches the posterior edge.
At ten years old C fig. 3. J the dividers are becom-
ing rounded, the central enamel is very near the
posterior edge and rounded.
At eleven years old C fig. 4. J the dividers have
become rounded, the central enamel is hardly any
longer apparent in the teeth of the lower jaw.
At twelve years old f fig. 5. J the corner teeth are
rounded, the central enamel has completely disap-
peared,+ the yellowish band is of more extent, and
* It is of a lighter color than the remainder of the ivory
that forms the wearing surface, undoubtedly because it has
existed a shorter lime. We remark in fact that the eburnous
substance becomes of a deeper yellow in proportion as it
becomes old ; it is of a milky white in very young teeth.
+ It disappears almost at the same time in all the teeih;
we should recollect the reason for this.
56
AGE OF THE HORSE.
occupies the centre of the wearing surface; the
central enamel remains in the teeth of the upper jaw.
At thirteen years old C fig. 6. J all the lower inci-
sor teeth are rounded, the sides of the nippers are
becoming longish, the central enamel remains in the
teeth of the upper jaw, but it is round and approach-
ing to the posterior edge.
At fourteen years old r fig. 7, J the lower nippers
have an appearance of being triangular, the dividers
are becoming long at the sides, the central enamel
of the upper teeth diminishes but still remains.
At fifteen years old f fig. 8. J the nippers are tri-
angular, the dividers beginning to become so, the
central enamel of the teeth of the upper jaw has
not disappeared as yet.
At sixteen years of age the dividers are triangular,
the corner teeth beginning to become so, the central
enamel of the teeth of the upper jaw will in many
instances be found to have disappeared.
At seventeen years of age C fig, 9. J all the teeth
of the lower jaw have become completely triangular;
but as we have before seen the sides of the triangles
are all of a length.
At eighteen years of age, the lateral portions of the
triangle lengthen in succession, first the nippers,
then the dividers, and afterwards the corner teeth,
so that at nineteen years of age the lower nippers
are flatted from one side to the other.
At twenty years of age, the dividers are of the same
sliape.
Finally, at twenty-one years of age this shape
appears in the corner teeth.
AGE OF THE HORSE. 57
After this period the incisors do not present any
distinguishing characters capable of directing us even
to an approximation; these teeth become flattened
more and more, and seem to converge towards each
other, touching merely by their lateral and anterior
edge; they become dried up, the gums become
whitened, the jaw bones become narrow, the tables
of the teeth become greyish, the incisors are yellow-
ish in the entire remainder of their extent, frequently
enveloped at their base by a thick layer of tartar,
whilst every thing announces in the individual old
age and fragility.
The continual growing up of the teeth of the horse
from the side next the root are such, that the socket
not being sufficiently long, the pressure of the new
portion of root pushes the tooth outwards. To this
consideration we should add, that these new portions
of teeth being always narrower, it becomes neces-
sary that the sockets should contract in order to hold
the tooth firmly from this narrowing, and the hori-
zontal direction of the jaws at an advanced age ; an
alteration well worthy of remark, which Tenon and
others have attributed to the manner in which the
jaws rub against each other ; whereas this action of
the jaws can only be considered as very secondary
in the production of these phenomena. Whatever
may be the explanation of it, it is invariable that
the sides of the superior maxillaries become flattened,
that the head seems to become lengthened and
pointed, which gives to the animal an oldness of look,
in which it is not easy to be mistaken. The horizon-
tal direction, owing to the same cause, is also always
58
AGE OF THE HORSE.
indicative of an advanced age; but this directiou
is very much pronounced in some horses, and not at
all in others; the cause of this remains a question.
To sum up, the incisor teeth of the horse remain
as guides long after the term assigned by the Greeks;
they mark throughout the whole of life, and they
indicate the different degrees of age up to twenty -one
years; first by the order in which they appear, second
by the obliteration of their outer cavity, third by the
changes and disappearance of their funnel, and
fourthly and lastly by the successive shapes that
iheir table takes on after nine years of age, and which
are the oval, the rounded, the triangular, and the
biangular. The appearance of the teeth, and the
obliteration of the mark, are without doubt the pe-
riods that furnish the most certain indications for
distinguishing the age. During the four or five years
that follow the obliteration of the mark, the know-
ledge of the age is still tolerably certain, because
there are many modes of correcting it ; such as the
state of the termination of the blind pouch, of the
funnel next the root, the general appearance of the
tooth, and the shape that the table of the tooth puts
on. The periods of triangularity and biangularity
present the greatest difficulties ; the data for these
latter periods are most commonly only approxima-
tions; nay, it is impossible to pronounce a positive
opinion on the age of a horse from sixteen years of
age to twenty. In conclusion, the different points
for consideration in the age of a horse, and to ren-
der them more concise and more easily comprehen-
ded, we have considered it right to construct the
AGE OF THE HORSE.
59
following table, which may be consulted in every
case. This table, the model of which is to be found
in Pessina, will have the double advantage of saving
the labour of seeking for observations scattered
through the body of this essay, and also of putting
the principles which it establishes within the com-
prehension of every person.*
* The different forms that the teeth take on are much less
regijlar in the corner teeth than in the nippers and dividers.
It is also necessary to observe, that in the following Table
we only speak of the incisors of the lower jaw : also that
the teeth do not pass suddenly from one form to another
these changes take place more or less slowly, are sometimes
earlier, and sometimes later, according to the density of the
substance of the tooth, and its power of resisting wear, ac-
cording to the nature of the food that the animal makes vse
of, and sometimes also according to the temperament of the
animal. To properly understand this difference, we have
marked in Italic letters the oval, the triangular, and bian-
gular, when commencing, and in Roman letters when these
forms are completed.
APPENDIX.
This appendix will form the completion of the
work on the age; it will include two principal
articles, in which is pointed out the most important
variations which the principles established on the
changes and successive shapes are capable of under-
going, and that the incisor teeth present.
••A
OF HORSES BADLY MARKED.
The incisor teeth do not push out and wear with
such regularity as the rules we have laid down in all
cases, and to all horses. Sometimes the appearance
of the incisors does not take place in the natural
order; at other times these teeth take a wrong direc-
tion ; some of the sucking teeth may also remain
and form supernumerary teeth, &c. These aberra-
tions of the teeth constitute horses badly marked or
hadli/ mouthed,^ and may arise from many causes.
First, — In the case where the teeth are faulty,
by being either too long or too short.
Second, — When the obliteration of the mark has
been irregular, and that the wear has not taken place
evenly on the table of the tooth.
* This expression is certainly trivial, and we have for a
long time hesitated to make use of it; but we could not find
another that conveys the same idea in a single word. In all
cases we say badly marked., or badly mouthed., but which should
jiot be confounded with bad mouthed, which is used to ex-
press horses that have oot been properly bitted.
F
62
APPENDIX.
Third, — Finally, whenever the appearance of the
teeth above the gum has sustained interruptions in
its progress.
Whether it is that some horses have the enamel
of their teeth harder than others, or that the increase
of the root exceeds the wear of the table, or, finally,
that the jaws have such a form and direction* that
the wear only takes place on the very table of the
incisor teeth; it is not rare for the incisors to pre-
serve a more or less considerably disproportioned
length, in such case it is certain that our principles
are not applicable, because they were founded on the
constant and proportional growth and wear of the
teeth. Pessina has sought to fulfil this object, and
if he has not entirely succeeded in it, he has at least
permitted himself to be corrected up to a certain
point. We may convince ourselves every day of the
utility of his data, although they only approximate.
* I have seen several horses in which one jaw was longer
than the other, in which case the incisor teeth acquire a very
great length, some, of them wear the anterior edge, and
others the posterior. It is generally the upper jaw that
exceeds, and in this case the superior incisor teeth become
curved at their anterior surface. There is then a continual
growth of them like the incisor teeth of rabbits (see Journal
de Physiologie, torn. 3, page 1.) and the development
that these teeth acquire in this latter animal, is owing perhaps
also entirely to tho disproportion in the length of the jaws.
There is at present in the museum of Alfort a jaw thus for-
med: it has but five upper incisor teeth. Sometimes there
is only a single tooth that becomes lengthened in this way.
We have spoken of this case, that we have already said is
more frequent in the molar teeih.
APPENDIX.
63
The length of the nippers being commonly about
eight lines, or rather better than three quarters of
an inch, that of the dividers about seven lines, and
the comers about six, let us take the medium for all
the teeth, we shall then have about seven lines out
of the gum from its edge to the wearing surface of
the tooth. According to Pessina, each tooth ought
to wear a line in well bred horses, and a line and a
half in common horses, each year ; at least such is
the case with those in whom the wear takes place
with the greatest regularity. If the portion of the
tooth that is seen out of the gum (always considered
generally for the facility of demonstration) is more
than seven lines in length, they have worn less than
they ought to have done, and the horse is conse-
quently older than the examination of his teeth
would lead us to suppose, but how much older is he ?
Each year the teeth ought to wear one line (I
suppose this case as being the most simple) they are
three lines too long, the animal would then appear
three years younger than he is in reality, and a trans-
Tcrse section would prove such to be the case.
From hence it follows, that to determine the age
of a horse whose incisor teeth are too long, we
should add to the age that the table of his teeth indi-
cate as many years as they have lines or lines and
half of too great length.
On the other hand, and for the same reason, the
horse whose incisor teeth are too short will appear
older than he is; and to determine his age we should
deduct as many years as the teeth are lines or lines
and a half too short. This is tolerably common in
f2
64
APPENDIX.
very old horses, whose teeth no longer retain any
enanafel; often also this shortness of the teeth is the
consequence of a sort of crib-biting, for which the
horse is returnable, simply because it does not leave
any particular trace of it.*
Undoubtedly if we wish to seek for scrupulous
exactitude in these observations, we shall not find
it; but where in all the principles in the knowledge
of the age of the horse does it exist to this degree!
Would it not be unjust to proscribe without mercy
all the observations of . Pessina, to go back to Lafosse
and copy him literally? Besides, we are not the
only persons who have reduced tho$e principles to
practice with advantage, and all Veterinarians will
ere long acknowledge how useful their application
may be.
These premises once acknowledged and admitted,
we shall not be embarrassed to pronounce upon the
age of horses naturally bishoped.+ This unnatural
permanence of the cavity, or of the extremity of
the blind pouch of the central enamel, that form
the two anomalies, cannot lead any person into error
* I should doubt if this is the case in England, where,
added to the glorious uncertainty of the law, we might per-
haps have the assistance of twelve tailors to determine a
horse cause. Transl.
+ I say naturally bishoped, because I never heard a word
in English that corresponds to the French begus, which is
said of horses that have the mark or cavit}^ so extremely
deep, that it remains for years after the imicA period. I
have seen many such cases. The French make two sorts
of it. Transl.
APPENDIX.
65
who does not express his opinion without an
attentive examination, having compared the shape
of the table of the teeth, their length, and, in fact,
the different characteristics of which we have
spoken.*
It is then quite possible to correct ourselves when
the teeth wear either too much or too little, pro-
vided the wear is regular; that is to say, when it
takes place on the wearing surface, and in the
manner we have pointed out. If, on the contrary,
the wear has taken place in such way as to destroy
the natural form of the tooth, we have no longer
any indication, except the freshness of the incisors,
tushes, &c. which happens when horses bite despe-
rately against the bottom of the manger, or upon
their collar shank. We can easily conceive that in
such case the vices in question would give rise to
the horse being returnable.+
When the range of the horse incisor teeth grows
up too far back it does not destroy the root of the
sucking teeth, nor compress their vessels and nerves;
neither does it destroy the septum, or partition of
* In fact, sometimes horses are naturally bishoped, par-
ticularly that sort called false, without the teeth being too
long. That arises, as we said before, in consequence of the
infundibulum being more or less prolonged, even in teeth of
an equal length.
+ As we here only speak of crib-biters so far as it aft'ecis
a knowledge of the age, we shall not go into any details on
this defect, which is in a greater or less degree injurious to
the horse's health, and which is communicated from one to
another by imitation, and not as has been said by contagion.
F 3
66
APPENDIX.
bone between them ; in a word, it does not cause
them to fall. These new teeth now form a double
row, which prevents the incisor teeth of the upper
jaw from rubbing against the table of the lower, and
gives to this surface such an irregular shape that it
is sometimes impossible to distinguish it. This is,
in every respect, the most difficult case, and we
must be satisfied to remain in the most perfect ig-
norance of it. Fortunately it is of very rare occur-
rence, and frequently there are only one or two
teeth that have not been forced out ; they then have
the appearance of a double tooth, which falls in the
course of time, and they do not, in any great degree,
impede our knowledge of the age.
TEICKS EMPLOYED BY DEALERS FOR THE PURPOSE
OF DECEIVING THE BUYER AS TO THE AGE OF
THE HORSE.
Dealers -are interested that the horses should ap-
pear most near the age when they are of the greatest
value, and when they can of course hope to get the
highest price for them. If the horses are too
young they endeavour to make them older in the
eyes of the purchaser; and, on the contrary, they
wish to make those that are older than they should
be, appear young.
In the districts where they breed horses, parti-
cularly in Normandy {qucere, in Yorkshire?) the
breeders frequently draw the sucking dividers, par-
•APPENDIX.
67
ticularly in colts that are backward,'^ and thus
cause the appearance of the horse incisor teeth
some months sooner. Those into whose hands the
same horses afterwards fall do the same thing with
the sucking corner teeth ; so that, although the horse
is no more than four and a-half years old, yet he is
furnished with all his incisor teeth. V/e have
pointed out, in speaking of the horse incisor teeth,
the means of avoiding falling into this error, against
which Veterinarians are not in general sufficiently
on their guard.
Immediately after these teeth have been drawn,
the place where the tooth that has been taken out
stood is more or less inflamed, bruised, and exco-
riated. In the order of nature, when the sucking
incisor teeth are fallen, the anterior edge of the
horse teeth appears immediately; this is not the
case until much later when the sucking teeth have
been drawn. It is, then, always easier to ascertain
to a certainty in the beginning; at a later period we
can only be guided by the season of the year in
which we may make our examination, and the more
or less advanced state of the horse teeth.
They frequently only draw the teeth of the lower
jaw ; and that is the true cause that in a great num-
ber of horses their appearance out of the gum pre-
cedes that of the upper incisor teeth; this is too
simple a case to be mistaken.
* An expression applied to distinguish horses the coming
forward of whose teeth is late or slow. In the contrary
case it is said that they are forward.
68
APPENDIX,
According to the opinion of SoUeysel and all other
Hippiatrists, the length of the teeth is an indication
of old age; and this opinion, though generally
adopted, is far from being always true. On the con-
trary, in very old horses, so far as we hare seen,
they become very short, at least when they have
not taken a completely horizontal direction. How-
ever, in admitting this to be correct in all cases, and
up to the most extreme old age, we must still be-
lieve that the animals would appear younger if we
saw their teeth ; and in this manner men? may be
imposed upon, who have only a superficial know-
ledge of the shape, the manner of growth, and the
wear of the incisor teeth; but it happens, precisely
on the contrary, that to a person acquainted with
the subject, they either show the exact age of the
horse, or else make him appear older than he really
is, and they make clear to him what he would
otherwise have been obliged to approximate to by
calculation.
Let us state an example, to make ourselves better
understood; suppose the mouth of a horse of which
we wish to ascertain the age, to be in the following
state : the lower nippers and dividers are rounded,
the central enamel is round, and very near the inner
edge of the tooth; the termination of the blind
pouch of the cavity next the root is very apparent ;
the animal is eleven years old. But his teeth are
ten lines long, instead of being only seven; he
appears then very old ; but suppose we were to sav/
them off, and take away three lines. The nippers
are triangular; the dividers are beginning t£) become
/
• APPENDIX. 69
so; the central enamel has totally disappeared; the
animal then marks fourteen years, which is his true
age, but which perhaps we should not have called
so much before his teeth had been sawed, because
then we had no means of correcting them but by
conjecture.
If the horse's teeth are not, or at least are not at
present, too long, it is necessary, for the purpose of
cheating the purchaser, to work a cavity similar to
that which had disappeared a shorter or longer tinie
previously, for the purpose of making him appear
as near six years old as possible, for it would be too
difficult to make him go back to five.
It is not necessary to enter into a detail of the
means employed to conceal this fraud, which some
dealers perform very skilfully, but can only deceive
those who have not studied the subject, or have had
but little experience. We know in fact that the
funnel that envelops the outer cavity, being the same
as the casing enamel, and of a substance harder
than the rest of the table, rises above its surface.
When the termination of the blind pouch of this
funnel remains, this cavity cannot be worked in the
middle;* they then bore it very near the outer edge
of the tooth: the position of this artificial cavity,
* We should not in fact consider as artificial a roundish
hole that is sonietimes found in the central enamel, and com-
municates with the interior of the root. We have already
seen, in quoting a passage from the letter of M. Girard to
M. Tessier, that the yellow spot which is only the termina-
tion of the blind pouch of the pulpy cavity, is replaced in
some old teeth by a hole of this sort.
to
APPENDIX.
and the existence of the termination of the blind
pouch of the central enamel on the table, suffices
to point out the fraud. If the animal is older, and
the central enamel has disappeared, the new cavity
is not surrounded by an exuberant edge; besides,
the general state of the jaw, and the form of the
tooth, are more than sufficient to determine our
opinion. Let us add to which, that the natural
cavity is always similar in form to that of the table
of the tooth, and which is not here the case.
EXPLANATION OF THE PLATES.
PLATE 1st.
The ten figures of the lower jaw, sketched in this
plate, exhibit the ten principal periods in the age
of the horse, from his birth up to eight years old.
The six teeth sketched separately, present the
exterior of the incisor teeth, as also their internal
organization.
Fig. 1. Jam of a foal newly horn ; the nippers
have made their full appearance, but they are still
a little on one side.
Fig. 2. In this jaw of from six to seven months
old, the nippers have already undergone wear to a
certain extent, and the inner edge of the dividers
is on a level with the outer edge.
Fig. 3. This figure expresses a foal of a year
complete; the corner teeth shot out about two or
three months, are nearly on a level with the divi-
ders, but they do not as yet present any appearance
of wear.
Fig. 4. A foal of two years complete ; the
nippers have the mark completely obliterated, and
the inner edge of the corner teeth is nearly on a
level with the outer edge.
EXPLANATION
Fig. 5. End of the jam of a foal of from
thirty months to three years old ; the nippers are
shot out within a short time, and their outer edge
has begun to wear. The wear of the sucking divi-
ders exhibits the bottom of the funnel.
Fig. 6. The state of this end of a jam marks
four years and a half old ; the horse dividers,
newly shot out, are still quite fresh, and not as yet
on a level with the nippers. The inner edge of the
latter are still untouched, and lower than the ex-
ternal edge. The sucking corner teeth are much
wx/rn, and present only the extremity of the funnel.
Fig. 7. A horse just closing up to five years
old ; the corner teeth have a short time shot out,
they are fresh and untouched ; the nippers begin
to lose the mark, the external edge of the dividers
has undergone some wear, but the inner is nicked^
as yet untouched, and lower than the outer.
Fig. 8. This figure represents the age of a horse
of six years ; the nippers have lost the mark, the
dividers have nearly so, but the inner edge of the
corner teeth are still untouched, and also slightly
nicked.
Fig. 9. A jaw in which the incisors mark
seven years old complete, and the nippers and
dividers have completely lost the mark, the inner
edge of the corner teeth is on a level with the outer,
in consequence of wear.
Fig. 10. In this jaw of eight years old all the
OP THE PLATES.
73
teeth have lost the mark, and the nippers begin
to assume the oval form, the remainder of the
funnel is close to the inner edge of the table of the
tooth.
Fig. 11. The tooth of a foal viemed at its pos-
terior or inner surface : a, the mouth of the cavity
or funnel of the table ; — b, the mouth of interior
cavity, or funnel next the root.
Fig. 1 2, Another foal's tooth viewed at the an-
terior surface, and in which we distinguish — a, the
body of the tooth ; c, the neck ; and b, the root.
Fig. 13. A very young foaVs tooth, in which
the casing or outer enamel is cut through its whole
length, showing the central enamel.
Fig. 14. A horse incisor tooth divided into two
parts throughout its length, and which shows the
external cavity, a ; cmd the internal cavity, b.
Fig. 15. A young horse incisor tooth, with an
opening made at the middle of the anterior surface,
leaving bare the lower portion of the funnel, a.
Fig. 16, A young horse incisor, sawed in the
same way as that represented fig. 1 4 :— a, the exte-
rior cavity ; h, the extremity of the funnel.
PXiATE 2nd.
The intention of the nine first figures of this
plate is to show the number of years after eight years
old ; and the sections of the tooth sketched in
Fig. 10 give an idea of the marks produced by the
funnel and the septum of the root.
74 EXPLANATION
Fig. 1. This jam belonged to a horse that was
eight years old off ; all the incisors have lost
the mark^ and the septum of the root appears on
the table of the nippers in tJie shape of a small
transverse zone, situate in front of the funnel, and
quite close to the outer edge of the tooth.
Fig. 2. The end of a jam of nine years old :
the nippers are rounded, and the dividers beginning
tv assume that form ; the remainder of the funnel
of these four teeth is round and quite close to
the inner edge of the tooth. These same teeth ex-
hibit the septum of the root, which is most pro-
nounced in the nippers.
Fig. 3. A jam of ten years old ; there is
merely the rudiment of the funnel in the nippers
as well as in the dividers, and the remainder of the
central enamel touches the inner edge of the table
of the tooth. The nippers and the dividers are
rounded, and the corner teeth present an oval form.
Fig. 4. From the state of the teeth of this jaw,
it had attained its eleventh year ; all the incisors
are rounded, and only now carry a slight trace of
the central enamel, which touches the inner edge of
the table of the tooth ; the septum of the root ap-
pears in all the teeth, and the j-emainder of the
funnel is smaller in the nippers than in the dividers
and corner teeth.
Fig. 5. In this jaw, which marks twelve years
old, the nippers have lost the central enamel, and
the septum of the root is rounded.
OF THE PLATES.
75
Fig. 6, This is aged thirteen years off ; the
nippers have become triangular, the dividers are
also assuming thatform^ and the corners are still
rounded. The septum of the root is rounded in the
four latter^ and is seen in the middle of the table.
The tushes are very much worn.
Fig, 7. The horse to whom this jaw belonged
might have been fourteen years of age ; the nip-
pers are triangular, and the dividers are becoming
so. The tushes are still more worn than in the
preceding figure.
Fig. 8. A jaw of fifteen years old off ; the
nippers and dividers have arrived at the period of
being triangular, and the septum of the root forms
a rounded point on all the tables of the teeth.
Fig. 9. These are teeth that indicate from fif-
teen to sixteen years of age ; all the incisors are
become triangular, and the nippers are beginning
to be flatted at the sides. The tushes are more
worn than in the preceding jaws.
Fig. 10. Exhibits six transverse sections of a
young horse incisor tooth ; the three first portions
a, b, c, have got the funnel, and the two last sec-
tions, d, e, show the septum of the root of the
tooth.
THE END.
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