Sect. XXVI. i. 4, OF GLANDS. a*y 



troublefome or noxious according to the importance of the func- 

 tions of the part affect eld : on the {kin and bronchia, where this 

 fecretion ought naturally to evaporate, it becomes fo vifcid as to 

 adhere to the membrane; on the tongue it forms a pellicle, 

 which can with difficulty be fcraped off; produces the fcurf en 

 the heads of many people ; and the mucus, which is fpit up by 

 others in coughing. On the noftrils and fauces, when the fe- 

 cretion of thefe capillary glands is increased, it is termed fimple 

 catarrh ; when in the inteltines, a mucous diarrhoea ; and in the 

 urethra, or vagina, it has the name of gonorrhoea, or fluor albus. 



A. When thefe capillary glands become inflamed, a {till more 

 vifcid or even cretaceous humour is produced upon the furfaces 

 of the membranes, which is the caufe or the effect of rheumat- 

 ifm, gout, leprofy, and of hard tumours of the legs, which arc 

 generally termed fcorbutlc ; all which will be trea ted of here- 

 after. 



II. 1. The whole furface of the body, with all its cavities and 

 contents, are covered with membrane. It lines every veffel, 

 forms every cell, and binds together all the mufcular and per- 

 haps the offeous fibres of the body ; and is itfelf therefore prob- 

 ably a fimpler fubftance than thoie fibres. And as the contain- 

 ing veffels of the body from the larger! to the leaft are thus lined 

 and connected with membranes, it follows that thefe membranes 

 themfeives confift of unorganized materials. 



For however fmall we may conceive the diameters of the 

 minuted veffels of the body, which efcape our eyes and gb.ffes, 

 yet thefe veffels mud confift of coats or fides, which are made 

 up of an unorganized material, and which are probably produ- 

 ced from a gluten, which hardens after its production, like the 

 filk or web of caterpillars and fpiders. Of this material confift 

 the membranes, which line the (hells of eggs, and the (hell itfelf, 

 both which are unorganized, and are formed from mucus, which 

 hardens after it is formed, either by the abforption of its more 

 fluid part, or by its uniting with fome ,part of the atmofphere. 

 Such is alfo the production of the fhells of fnails, and of fhell- 

 fiih, and I fuppofe of the enamel of the teeth. 



2. But though the membranes, that compofethe fides of the 

 moft minute veffels, are in truth unorganized materials, yet the 

 larger membranes, which are perceptible to the eye, feem to be 

 compofed of an intertexture of the mouths of the abforbent fyf- 

 tem, and of the excretory ducts of the capillaries, with their con- 

 comitant arteries, veins, and nerves : and from this con flruct ion 

 it is evident, that thefe membranes mult poffefs great irritability 

 to peculiar hamuli, though they are incapable of any motions, 

 ihat are viable to the naked eje ; and daily experience fhews us, 



tha£ 



