V 
30' ADescriptionofallthe Sed. VII. 
that I have not yet been able to get a diftind view of them, though I employed 
magnifying glalTes (>6). 
These fimbriae feem therefore to bedu6ls like to thofeof the urethra, which 
prepare a mucilaginous liquor without the afiiftance of any knotty or glandular 
organ. While by the prelTure which the motion of the joints or tendons . 
makes upon their fides, they throw out their liquor in greatefi: quantity when 
it is moft needed, perhaps the fecretion, as well as excretion, of the liquor, is - 
promoted, as in the falivary glands, by motion; and as the extremities of 
thefe fringes hang loofe into the cavity of the joint, their liquor cannot be 
preffed back into them by the motion of the joint. 
Upon the whole, the fynovia feems to be furnilhed by invifible cxhalant ar- 
teries, by the duds of the fimbrise, and by oil exfuding from the adipofe fol- 
licles by palTages not yet difcovered. We may fuppofe thefe pallages to be 
very minute, not only becaufe they are not to be feen with the microfcope, 
but becaufe the oily matter is fo well incorporated with the mucilaginous 
as not to be diftinguilhable, even with the microfcope, in the form of glo- 
bules. 
As the fat feems to be mixed and incorporated with the mucilage in thefe 
lacs, it would perhaps be more proper to name them vejtccs ungulnofay than 
burfie mucofae. 
lo. Having fully confidered the ftrudure of the burfae and ligaments in a . 
found date, we lhall next dired our attention to the effeds upon them of ufe, 
accident, operation, and difeafe ; by which we fhall be more fully convinced of 
the famenefs of their ftrudure and properties. 
In old perfons^ I have frequently found a hole worn in the membrane of a 
burfa and ligament which were contiguous, particularly at the joint of the 
. thigh- 
(h) See tlieir ftrudure delineated in Tab. VIII. from fig. i. to fig. 1 8. 
