The involuntary excretion of the semen, the morbid pollution, may take place sometimes in the manner described, sometimes in another mode. In the first case, it differs from what occurs in the normal state, only not being preceded by those acts which are performed voluntarily by man. Secondly, the semen is excreted without any convulsive effort; it flows like the tears, the saliva, the bile. The semen comes into the urethra, and escapes from it merely because it is there. There is no ejaculation: and this is easily conceived of; for the genital organs are not sufficiently excited, to cause the ejaculatory powers to be convulsed, as is proved by the excessive weakness of the venereal sensation. And, secondly, one of the indispensable conditions of the ejaculation--erection of the penis--does not exist. There are, then, two kinds of involuntary pollutions; one which is _convulsive_, and the other which is _not so_. Between these two kinds, there are intermediate degrees, in which spermatorrhœa partakes more or less of one or the other. These degrees often mark the passage from convulsive spermatorrhœa to that which is not convulsive; for the latter has generally been preceded by the former. We shall see hereafter, that the existence of one of these affections does not forbid that of the other; and that the ejaculation of semen is possible in some individuals who present habitually an insensible flow of this fluid.
Involuntary pollutions have been distinguished until now in another manner: they have been divided into _diurnal_ and _nocturnal_. These distinctions are founded only on accessory circumstances. What difference does it make, whether the pollutions occur by night or by day, provided they are similar in other respects? If, on the contrary, there are more essential differences, why not give to them the importance they demand? Farther: is not convulsive spermatorrhœa, like that which is not convulsive, seen both at night and day? These are the reasons why we have sought to distinguish these affections more logically, and which have led us to propose the new distinction just mentioned.
Convulsive spermatorrhœa may occur in all individuals, and under the influence of a great many causes, without being necessarily a disease. After excessive continence, it may even prove a salutary crisis. This pollution has a pathological character, when it is repeated too often, or under unfavorable circumstances; and then it produces the same result as excesses in coition or masturbation, and generally occurs only in individuals already enfeebled by this kind of excess. Sleep is the most favorable state for an attack of spermatorrhœa; and from this circumstance it is called nocturnal pollution. The temperature of the bed, and lying on the back--circumstances which favor the warmth and excitement of the lower part of the spinal marrow--may also cause the convulsive excretion of the semen. But another cause of it is, that during the sleep of the external senses, the internal senses have control, and have more power, because the action of the others is completely suspended. Cabanis remarks this fact, in saying that the genital organs do not participate in the repose of the external senses, but seem to be more excitable when these are asleep. We consider, that what takes place then is analogous to what is observed in idiots, who, deaf, blind, and dead to all the feelings of relation, abandon themselves to every excess, to satisfy a sense, the excitement of which in them often amounts to constant satyriasis.