island is nearly unmixed, they, are, in general, people of short-
stature, small limbs and-features? where they are intermixed
with English settlers or with the Lowlanders of Scotland, the
people are remarkable for fine figures, tall stature, and great
physical energy. It would be easy to multiply instances of
this description, but I shall not proceed further at present.
On a review of all the facts connected with the propagation
of mixed breeds we may conclude, that real hybrids are
either barren or so little prolific that their stock is destined
soon tojppqmp extinct, while the mixed offsprings originating
from different races -within the limits of the same species
generally exceed 4n vigour and in the tendency to multiplication
the parent races from which they are produced. I
do not wish to erect an important conclusion upon this one
argument, but itS'evidence as far as that extends, and considerable
weight will be allowed to it, is manifestly favourable
to the doctrine that the several tribes of men are but varieties
of the same species.
S ection VI.— Third Head o f the Analogical Investigation
o f Species.—Pathological Considerations.
It has been well observed by a celebrated German physician,
C. W. Hufeland, that the comparative pathology of
living tribes and species must be more attentively studied and
more fully elucidated than it has yet been, before we can
render complete our acquaintance with their physical history.
The diseases and predispositions to disease peculiar to certain
races, constitute as much a part of the physical-description
and enter as fully into the aggregate of distinctive characters
belonging to these races, as any feature in their anatomical
structure. It is much to be regretted, thaVthe sources of information
are very defective in reference to this subj ect. We
are only enabled to collect facts which are as yet so few and
so imperfectly understood, that they sometimes appear discrepant
and contradictory in their bearing. This is particularly
the case with respect to the inferior tribes of the animal
creation, and the reasons are so obvious, that they do not
require to bp? specified. The pathology of these tribes is so
imperfectly known, that we are* not enabled' to deduce from
this quarter amy-gcperal inferences which may be afterwards
compared with, and' may tend to elucidate the bearing of analogous
facts collected from the-history? of mankind. The pathology
of human races is somewhat more advanced, and the
facts related to ityrCst om-dess doubtful authority, but they
are of very limited extend®
Paragraph 1|—Of contagious and ppid§mic diseases.
; Observations on -.contagious y diseases)* or on complaints
which am. capable of spreading frpm .onj^jihrln idualAo.vser a.
whole community, may throw some,»fight on .the limitations. of|
species. IT it should he proved, that tlü| influence pfrmorbid
poisons is? in general, confined tpvsqme. particular râpes and
is destitute of agency e^. others sp§cips,dn( ^® jE ^ e v ^ |J.to.
tribes thgL motet nearly approaching in form and,, organization,,
W£ might avail, -qi|rrelyqs of this -fact, as a criterion b y -which
thp-cmg^tipni m ig h t.d e te rm in e d with some degree pf.prob.a-,
bility, whether all human races originate from the fame sfock.;
The state of knowledge on this sqjbjep! is nçesept^too imperfect
to. warrant any positive conclusions.
. It jSi- indeed, weltknoxyn, that some contagious diseases,are;.
communicable from one tribepf animals tp^npjther^po w,-pox
affords the most familiar, example. Without assuming^ to,
he a certain fact, that this, disease is|Mentic.al with that which
in parses, ijp termed the grease, and that if has been-.cgmmuni-
cated from the horse to the cow through human intervention,
points which hqye been, however, in my-opinion, fully,.-established
jyy D.r. Baron,,.it is certain, Ipcpss, the dog, the
goaf;, and the sheep arp, capable qfijreceiying^tbp;yacçine disease
by inoculation, and that matter taken from pustules so
* In the category of contagious diseases, I mean, in orderjto preclude all’con-
troversy, to comprise only such distempers as are considered, like small-pox and
measles, to arise solely from contagion. Diseases which are thought to become-under
particular circumstances infectious Or capable of spreading, of which the class is
very indeterminate, are not meant to he included under the term adopted in the text.