From all which it appears, that the pain felt by infants soon after their birth, and which they express by crying, is a sensation merely corporeal, similar to that of other animals, who also cry the minute they are brought forth; as also, that the mental sensations do not begin to manifest themselves till forty days have elapsed; smiling and weeping being produced by two internal sensations, which both depend on the action of the mind. The former is the effect of an agreeable emotion, which can only arise from the sight, or resemblance of an object known, beloved, and desired; the latter is that of a disagreeable impression, compounded of sympathy, and anxious concern for ourselves; both imply a certain degree of knowledge, as well as an ability to compare, and to reflect. Smiles and tears, therefore, are signs peculiar to the human species, for expressing mental pleasure or pain; while cries, and the other signs of bodily pain and pleasure, are common to man, and to the greatest part of the animal creation. But let us return to the material organs and affections of the body. The size of an infant born at the full time, is usually about twenty-one inches; this is not without exception, some falling short of and others exceeding this measurement. In children of twenty-one inches, the breast, measured by the length of the sternum, is nearly three inches; and in those of fourteen, only two inches. At nine months, the foetus generally weighs from twelve to fourteen pounds. The head is large in proportion to the rest of the body; but this disproportion gradually wears off as the size of the child increases. Its skin is very soft, and from its transparency, by which the blood beneath appears, it is also of a reddish cast. It is even pretended, that those children whose skins are the most red when born, will afterwards be the fairest, and the most beautiful. The form of the body and the members of a new born infant, are by no means perfect: all the parts are too round, and even when the child is in good health, they seem swelled. At the end of three days, there generally appears a kind of jaundice; and at this time there is generally milk in the breasts of the infants, which is squeezed out with the fingers. The superfluous juices, and the swelling of the different parts diminish by degrees, as the child increases in growth.