astride any hard substance, blows, wounds, contusions occasioned by riding, the presence of foreign substances, the injudicious use of injections, and lastly, which is as frequent a cause as any one of those heretofore enumerated, _masturbation_. The violent manual efforts made by a young sensualist to procure the sexual orgasm for the third or fourth time continuously, I have known to be of that degree that irritation has been communicated to the whole length of the urethra, extending even to the bladder; and retention of urine, in the instance I allude to, ensued, and required much attention before it could be subdued. Excessive intercourse with females will give rise to the same effects; not so likely as in the case preceding, inasmuch as the former can be practised whenever desired, while the latter needs a participator. The act of masturbation repeated, as it is, by many youths and others, day after day, and frequently several times within each twenty-four hours, must necessarily establish a sensitiveness or irritability in the parts, and alteration of structure is sure to follow. The positive changes which take place in stricture in the urethral passage are these: there ensues a thickening and condensation of the delicate membrane and the cellular tissue underneath, which may possibly unite it to the muscular coat. This thickening or condensation is the result of what we call effusion of coagulable lymph. It will be rather difficult to explain the process; but lymph is that fluid understood to be the nutritious portion of our sustenance or system, and which is here yielded up by the vessels which absorb it, and which vessels abound, with few exceptions, in every tissue of our body. However, it will suffice to say, that where inflammation takes place, there is an alteration of structure, and that alteration is generally an increase. In stricture, this increase or thickening takes place, as I observed before, in particular parts of the urethra, but where the inflammation is severe, no part is exempt, and whole lengths of the passage become occasionally involved. It is true, certain parts are more predisposed than others, as, for instance, the membranous, bulbous, and prostatic portions of the canal; but there are oftentimes cases to be met with where these parts are free, and the remainder blocked up. This effusion or thickening assumes various shapes, and selects various parts of the urethra. The subjoined diagram will convey a tolerably perfect idea of the malady in question; indeed it is a beautiful specimen of simple stricture. [Illustration: A—The cut edges of the corpus spongiosum. B—The urethra. C—The stricture.] To continue the description of the formidable consequences of neglected stricture.