In relation to sterility, I would here bring to mind, what has before been stated, that a woman is most likely to conceive immediately after a menstrual turn. And now, also, let me suggest the idea that Nature's delicate beginnings may be frustrated by the same means that put her a going. This idea is certainly important when the woman is known to have miscarried a number of times. Sterility is sometimes to be attributed to the male, though he apparently be in perfect health. It would be an interesting fact to ascertain if there be no seminal animalculae in these cases; and whether medicines of any kind are available. It has been ascertained that a male and female may be sterile in relation to each other, though neither of them be so with others. The foregoing measures for sterility are also suitable in cases of impotency. This term, I believe, is generally con-lined to, and defined as a want of desire or ability, or both on the part of the male; but I see no good reason why it should not comprehend the case in which there is neither desire nor pleasure with the female. Such females, it is true, may be fruitful; but so, on the other hand, the semen may not have lost its fecundating property. Impotency, at a young or middle age, and in some situations in life especially, is certainly a serious misfortune, to say the least of it. The whole evil by no means consists, in every case, in the loss of a source of pleasure. All young people ought to be apprised of the causes of it--causes which, in many instances, greatly lessen one's ability of giving and receiving that pleasure which is the root of domestic happiness. I shall allude to one cause, that of premature, and especially solitary gratification, in another place. Intemperance in the use of spirits is another powerful cause. Even a moderate use of spirits, and also of tobacco, in any form, have some effect It is a law of animal economy, that no one part of the system can be stimulated or excited, without an expense of vitality, as it is termed. The part which is stimulated draws the energy from other parts. And hence it is, that close and deep study, as well as all the mental passions when excessive, impair the venereal appetite. All excesses, all diseases and modes of life which impair the general health, impair this appetite, but some things more directly and powerfully than others.