This great number of secretory organs, constantly engaged in separating 

 various secretions from the mass of the fluids, would soon exhaust it, if 

 the calculations of physiologists of the amount of what a gland is capable 

 of secreting, were not manifestly exaggerated. In fact, if w,e admit, with 

 Haller, that the mucous glands of the intestinal canal secrete, in twenty- 

 four hours, eight pounds of mucous; that, in the same lapse of time, the 

 kidneys secrete four pounds of urine,- that the same quantity is lost by the 

 insensible perspiration; and again, as much by the pulmonary exhalation; 

 there will be lost, daily, twenty pounds of fluids, almost entirely excre- 

 mentitious; for we do not include in that calculation the bile, the tears, 

 nor the saliva and pancreatic fluid, which, in part, returns into the blood 

 after being separated from it; nor the serum which moistens tl|e internal 

 surface, and which is purely recrementitious. 



This exaggeration, in the calculations of the fluids which ,are daily- 

 poured out by the different emunctories, is to be attributed to the%:ircum- 

 stance of having taken the maximum of each secretion, without consider- 

 ing that they mutually supply each other; so that, when less urine is void- 

 ed, the quantity of perspiration is greater, and vice versa. It is very 

 well known, that a violent diarrhea is frequently the consequence of sud- 

 den cold applied io the skin ; the fluids at once repelled towards the in- 

 testiual canal, having to pass through the mucous glands whose action is 

 greatly increased. 



CII. It has been customary to enumerate, among the glands, certain 

 bodies which have truly a glandular appearance; but the uses of which 

 are yet unknown. Thus, the thyroid and thymus glands, which are pa- 

 renchymatous organs destitute of excretory ducts, though receiving many 

 vessels and some nerves, do not appear to secrete any fluid. But may not 

 the blood, which is conveyed so plentifully to the thyroid gland, undergo 

 nevertheless certain changes, though we may not be able to discover 

 what they are? Besides, may not the lymphatics perform the office of 

 excretory ducts, and convey back again immediately into the mass of the 

 blood, the fluid which has undergone changes in the glandular body? The 

 capsulse renales are in the same condition: they have, however, in addi- 

 tion, an internal reservoir, a kind of lacuna, whose parietes are smeared 

 with a viscid and brown-coloured substance secreted Ay the capsule, and 

 which doubtless is conveyed into the mass of the bipod by the lymphatics 

 arising from the parietes of its internal cavity. 



CHI. Of the secretion ofadeps within the cellular tissue. This soft tissue, 

 which is diffused over the whole body, and a#>rds a covering to all our 

 organs, is of use not merely in separating ^em from one another, and 

 connecting together the different parts; it j/ besides, the secretory organ 

 of the adipose substance, a semi-concrete/oily, animal substance, which 

 is found, in almost every part of the bo/y, deposited in its innumerable 

 cells. The membranous parietes of these small cellular cavities are sup- 

 plied by numerous minute arteries, i/i which the adeps is separated; it is 

 conveyed by its specific light weight to the circumference of the column 

 of blood in the vessels, and transudes through the pores in their parietes. 

 Its quantity and consistence vary, in different parts of the body, and in 



have both a large plexus of nerves and a ganglion, whence their nerves are exclusively 

 derived, arid which appear to be entirely devoted to the functions of the viscus, whose 

 blood-vessels they plentifully supply. See, on this subject, the APPENDIX, Notes H, 

 A, A, and those on Digestion, Sac.-*- Copland. 



