Rickets may also produce the same effect. There is a skeleton of a rickety child in the French king's cabinet, whose arms and legs have callosities in the middle of their bones. By the inspection of this skeleton, it appeared evident that the bones had been broken during the time it was in the womb, and that afterwards the bones re-united, and formed these callosities.
But enough of a subject which credulity alone has rendered marvellous. Prejudice, especially that sort which is founded on the marvellous, will always triumph over reason, and we should have but little philosophy if we were astonished at it. We must not therefore ever expect to be able to persuade women, that the marks on their children have no connection with their unsatisfied longings. Yet might it not be asked them, before the birth of the child, of what particular longings they had been disappointed, and consequently what will be the marks their children will bear? I have often asked this question, and have only made persons angry without having ever convinced them.
The time that a woman goes with child is generally about nine months; but it is however sometimes longer and sometimes shorter. Many children are born at seven or eight months, and some not till after the ninth; but in general the deliveries which precede the term of nine months are more frequent than the others. The common time of a natural delivery extends to twenty days, that is, from eight months fourteen days to nine months and four hours.
Many children are born before the 260th day, and although these deliveries precede the general term, they are not abortions, because these children mostly live. It is commonly thought that children born at eight months cannot live, or at least that many more of them die than those born at seven months. This opinion appears to be a paradox; and by consulting experience I think we shall find it an error. The child brought forth at eight months is more formed, and consequently more vigorous, and likely to live than that which is born at the seventh. Nevertheless this opinion is pretty generally received, and founded on the authority of Aristotle.
The beginning of the seventh month is the earliest term for delivery; if the foetus is brought forth sooner it dies, and is termed an abortion. There are, however, great limits for the time of human delivery, since they extend from the seventh to the tenth, and perhaps to the eleventh month.