AS DURING the development of the foetus (see chapter 3) our two kidneys represent only an improved form of the two embryonic Wolffian bodies, so also both the excretory systems are quite similar, and the mechanism of the urinary and seminal secretions almost identical. I therefore beg the reader to consider this chapter not only as concerning the urinary secretion, but also with respect to the seminal secretion as well; a distinct economy, as otherwise it would have had to be printed and read twice over.
We are all familiar with the distressing spectacle of a child who has not had a timely opportunity to urinate. He becomes more and more uneasy and fidgety, squeezes his legs together, as though that will help his occlusory musculature; he twists and turns in all directions in the effort to relieve his pain and trouble. It is quite impossible for him to fix his interest on anything whatever; the more acute the antagonism grows within him, the more excitable and nervous he becomes; and how congested is his troubled little face! At last all his nerve centres are overwrought, all the muscle-groups of his body twist in clothe spasms, and so we see the trembling, convulsive picture of a maximal hypertension. He bursts into pro-fuse perspiration until at last, perhaps quite unexpectedly, often because the occlusory muscles have relaxed their energy for an Instant, the expulsory musculature wins the day and the urine flows unhindered. The bladder is relieved; only the child’s clothing is wetted.
The true significance of this finale as the climax of the peristalticsecretory function of the whole excretory apparatus only appears convincing when we study it by the comparative method with the seminal secretion, because here, on account of the small volume of the fluid to be voided, the whole secretory function is only manifested in this finale.
With this normal scheme of the urinary secretion in view we should, however, be far from the truth if we imagined that the sensation of desire to urinate is always proportional to the amount of urine actually in the bladder. In the first place we can voluntarily increase the impulse when we submit the bladder to increased mechanical pressure through contraction of the abdominal musculature. Even a distension of the lower bowel may mechanically increase the pressure on the bladder and cause a precipitate desire to urinate.
Besides which, the irritability of the bladder-wall may be artificially increased by the employment of the substances which we have already mentioned.
We mentioned them then because they increase the amoubt of urine, and we refer to them again here, because at the same time they may rendcr the bladder-wall excessively irritable and congested, In serious cases the irritability of the bladder-wall may be greatly increased, if through the ingestion of irritating drugs or through chill or infection, etc., a regular catarrh of the mucous membrane has been set up. In such a case the smallest traces of urine in the bladder may occasion the most powerful and painful contractions of the bladder-wall, as if it were greatly distended. Just as in conjunctivitis, a tear-drop in the eye may be as intensely painful as if grains of sand had blown in.
And if one devotes special attention to the dcsire to urinate this impulse is felt sooner and more powerfully; for instance when a schoolboy holds up his hand in class to ask permission to leave the room, all the other boys suddenly feel the same desire. The same happens if one accidentally sees someone else urinating, or even suddenly thinks of this function.
In all these cases it is the imagination that acts as an irritant.
If then, in practical life, we seriously ask ourselves the question: is the impulse that I feel at this moment only the result of an accidental stimulus, or is it really the voice of Nature telling me not to neglect this important function, how can we obtain an answer?
It is not always an easy matter to settle this problem. With a Iittle observation and experience we shall be able in most cases to decide *hat influences are active in any particular instance. Furthermore, there is frequently a posteriori a very good criterion already in existence, which may serve as precedent. When a real over-distension takes place, if we do not obey the impulse with physiological regularity, it will burden us increasingly until finally the secretion ceases. If, however, the stimulus is only accidental, then the impulse may perhaps be momentarily much more powerful and peremptory than usual, but never with this regular periodicity; and if we do not yield to it, then in a short time the impulse decreases, far sooner and more permanently than if we had yielded to it immediately.
We can also formulate the same principle in the positive sense: after a suitable satisfaction, we experience an appropriate period of rest; after over-stimulation, if we yield, the impulse will always disturb us more capriciously and no longer allow us to rest.
With all these causes of artificial over-stimulation, a regular, suitable satisfaction, together with a regular and frugal diet can work wonders. Strength of will, exercise and self-control prepare the way. And the more earnestly we look upon life, the more shall we avoid both clangers: excess and insufficiency. We must control our reflexes, but this control should never be abused, and the function deliberately repressed.
If, however, one attempts too great a repression of this function, then after a few periods of rest, the impulse is felt again still more imperiously until finally a period of morbid exhaustion sets in, and the impulse really considerably diminishes; and one is as pleased with his victory as the peasant, who wanted to cure his horses of the bad habit of eating was at first with his success. But one should never forget that such attempts to circumvent Nature lay the foundation of paralytic conditions, and cause much suffering later on.
To suppress the function permanently is impossible. Finally the internal tension must become overpowering, and the occlusory muscles are forced to give way. The product of secretion then flows out, voluntarily or involuntarily, but flow it must. As long as we are able to think for ourselves, we must see to it that no injury ensues from it, either for ourselves or for others. And for this reason Part III is devoted to the problems of self-control.