AND AMERICAN RURAL SPORTS. 
273 
is also inserted into the os calcis.. It is to be observed, 
that the origin of the latter was anterior to that of the for- 
mer, but its insertion posterior, so that these lateral liga- 
ments cross each other in the form of an x • The external 
articulating protuberance of the astragalus on which the 
tibia revolves, has, as has been already stated, a nearly cir- 
cular outline, and the attachments of the ligaments just 
described, are at points on the outside of the os calcis, which 
would lie nearly in the circumference of that circle, were 
it continued from the articulating surface; so that each of 
these ligaments has one of its extremities fixed in a certain 
point of the circumference, while its opposite extremity re- 
volves during the motion of the joint, nearly in the circum- 
ference of the same circle. This observation applies like- 
wise to the two lateral ligaments on the inner side of the 
joint, which have nearly the same relation to each other, 
and to the general contour of the joint, as that just des- 
cribed; so it is obvious, that during the rotation of the 
joint, as the origins of these ligaments move along the same 
circumference in which their attachments are fixed, the 
ligaments will be most stretched when they correspond to 
diameters of that circle. 
Now it is so arranged that this happens at the same time 
for all, and consequently the ligaments on each side corres- 
pond not merely as to direction, but as to the point of time 
they become most stretched, which is nearly at the moment 
that the joint has no tendency to move either way, and at 
that moment, it is to be observed, that although the liga- 
ments are most tense, and of course react on their points of 
attachment with greatest force, yet this produces no motion, 
as the force is exerted in a direction perpendicular to the 
circumference; but as soon as the tibia is moved beyond 
this point of inaction for the ligament, the latter, no longer 
representing diameters, by their contractile force evidently 
tend to accelerate the motion; and as they all act in the 
same direction, and are assisted by the shape of the articu- 
lating surfaces, a sudden motion of flexion or extension is 
thus produced. 
The preceding explantion supposes the ligaments to pos- 
sess, contrary to the nature of ligaments, in general, a cer- 
tain degree of elasticity, which was evidently the case in 
all, but particularly in the most deep-seated of those on 
the inner side of the joint, which, therefore, appears most 
concerned in producing the sudden motion, whether of 
flexion or extension. — Edin. Philos. Jour. 
There is no fish which yields so much oil in proportion to 
its size, as the Porpoise, and therefore renders its capture 
an object of consideration; and it is said, that whenever a 
Porpoise happens to be wounded, all the rest of its compa- 
nions will immediately fall upon, and devour it. 
3 Z 
THE BREAD FRUIT. 
The bread-fruit, originally found in the south-eastern 
parts of Asia, and the islands of the Pacific, though now in- 
troduced into the tropical parts of the western continent, 
and the West India islands, is one of the most interesting, 
as well as singular productions of the vegetable kingdom. 
There are two species of it: the bread-fruit, properly so 
called ( Jlrtocarpus incisa ), with the leaves deeply gashed 
or divided at the sides, which grows chiefly in the islands; 
and the Jack fruit, or Jaca tree ( Artocarpus in;tegrifolia,) 
Avith the leaves entire, which grows chiefly on the main 
land of Asia. 
The bread-fruit is a beautiful as well as a useful tree: the 
trunk rises to the height of about forty feet, and, in a full 
grown tree, is from a foot to fifteen inches in diameter; the 
bark is ash-coloured; full of little chinks, and covered by 
small knobs; the inner bark is fibrous, and is used in the 
manufacture of a sort of cloth; and the Avood is smooth, 
soft; and of a yellow colour. The branches come out in a 
horizontal manner, the lowest ones about ten or twelve feet 
from the ground; and they become shorter and shorter as 
they are nearer and nearer the top: the leaves are divided 
into seven or nine lobes, about eighteen inches or two feet 
long, and are of a lively green. The tree bears male and 
female flowers, the males among the upper leaves, and the 
females at the extremities of the twigs. When full grown, 
the fruit is about nine inches long, heart-shaped, of a green- 
ish colour, and marked with hexagonal warts, formed into 
facets. The pulp is white, partly farinaceous and partly 
fibrous; but, when quite ripe, it becomes yellow and juicy. 
The whole tree, when in a green state, abounds Avith a viscid 
milky juice, of so tenacious a nature as to be drawn out ‘in 
threads. 
In the island of Otaheite and other places, where the 
bread-fruit forms the chief support of the people, there are, 
as is the case with cultivated vegetables in all countries, 
many varieties; only two, however, are very different from 
each other — that which contains seeds in the fruit, and that 
which contains none. The variety with seeds is much in- 
ferior to the other, being more fibrous, containing less farina, 
and not so pleasant to the taste; it is, therefore, not culti- 
vated, though, in cases of need it is roasted and eaten. 
Whether the seedless sort has been produced wholly by cul- 
tivation it is not easy, and would not be of much importance, 
to ascertain: it is the one cultivated in the South Sea is- 
lands; it was originally found only there; and the tree was 
not in much repute till these islands were discovered. 
The bread-fruit continues productive for about eight 
months in the year: such is its abundance, that two or three 
trees will suffice for a man’s yearly supply, a store being 
