416 OF SECRETION. 



merit must then be directed towards the diminution of the quantity pro- 

 duced. Thus the tendency to lithic acid deposit may be frequently 

 cured, by simply diminishing the quantity of azotized matter in the 

 food ; and the undue formation of the phosphates may be often kept in 

 check by that mental repose, which is peculiarly required after long- 

 continued and severe exercise of the intellectual faculties, or strong ex- 

 citement of the feelings. 



741. There is no doubt whatever, that the total suspension of the 

 Urinary secretion is productive of rapidly-fatal results, from the accu- 

 mulation of the elements of the secretion in the blood ; and it would 

 appear, that the tissue on which their presence in the circulating fluid 

 exerts the most injurious effects, is the Nervous. It is probable that 

 Urea is the substance which is most directly concerned in producing 

 the noxious influence ; and we see an effort made by the system (so to 

 speak) to get rid of it, in those cases in which a discharge of urinous 

 fluid takes place by unusual channels, such as from the mucous mem- 

 brane of the stomach, the mamma, the umbilicus, the nose, &c., when 

 the usual secreting action of the Kidney has been suspended. Although 

 the accounts of such cases have been treated with ridicule by some 

 Physiologists, yet there seems no valid reason to discredit them, when 

 it is borne in mind that, in persons who have died from the complete 

 suspension of the secretion, effusions containing urea have been found 

 in the serous cavities of the trunk, and in the ventricles of the brain. 

 The poisonous influence of an accumulation of urea in the blood, when 

 strongly exerted, produces in the first instance irregular or convulsive 

 movements, which are dependent upon irritation of the Spinal system 

 of nerves ; then loss of consciousness, depending upon the suspension of 

 the powers of the Brain ; and lastly, complete suspension of the powers 

 of the spinal system, so that the ordinary reflex actions cease, and life 

 becomes extinct from the stoppage of the respiratory movements ( 688). 

 There is reason to believe, that many convulsive motions, for which no 

 obvious cause can be assigned, have their origin in a disordered condi- 

 tion of the blood, resulting from imperfect elimination of Urea ; thus it 

 has been ascertained that, in several cases of puerperal convulsions, 

 urea was present in the blood; the functional power of the kidney 

 being diminished by chronic disease. It is especially to be noticed, 

 that most of the cases in which, the urinary secretion is discharged 

 through some irregular channel, occur in persons who have been sub- 

 ject to those convulsive affections, which are commonly designated as 

 hysterical ; and that the discharge of a large quantity of urine through 

 the natural channel, is often the termination of an hysterical paroxysm. 

 It is desirable, therefore, that in all such obscure cases, the state of the 

 urinary secretion should be carefully looked to. 



4. Of the Cutaneous and Intestinal Glandulce. 



742. The Glandulse which are disposed in the substance of the Skin, 

 and in the walls of the Intestinal canal, although individually minute, 

 make up by their aggregation an excreting apparatus of no mean im- 

 portance. The Skin is the seat of two processes in particular ; one of 



