670 PHILOSOPHICAL TKANSACTION8. [aNNO I769, 



brane, behind the internal coat of the bladder, and seem to join with the Jym- 

 phatics of the vesiculae seminales, to be continued with them to the neighbour- 

 ing glands, and so on to the thoracic duct- 



I have not been able to find lymphatics in any other part of the urethra; indeed 

 this canal seems to be perfectly void of them till we come to its membranous 

 portion, where we meet with these I have been describing; and it may be re- 

 marked, that here they are placed in that part of the urethra where the greatest 

 quantity of moisture is supplied. Very probably the sealing up the mouths of 

 these delicate vessels, by frequent inflammation and induration, may give rise to 

 that obstinate stillicidium which is seldom if ever cured ; owing to an accumu- 

 lation of thin fluids, with a faulty absorption. 



These lymphatics of the urethra and bladder also point out the road, by which 

 any subtle virus may pass, with the lymph, directly into the mass of blood, and 

 contaminate the whole habit, without giving the least appearance of any local 

 disorder. To have a clearer idea of the vessels I have been treating of, I must 

 beg leave to refer to the drawing annexed, in which these lymphatics of the uri- 

 nary bladder and urethra, in the human body, are carefully and very accurately 

 delineated. 



Fig. 1 1, pi. 17, is an exact representation of the lynnphatics of the urethra and neck of the bladder, 

 as they appear after having been injected with mercury, and preserved in spirits. 



A is the membranous portion of the urethra slit open, b b, bristles in the ducts from the vesiculae 

 seminales. cc, the prostate gland, dd, the inferior part of the bladder laid open, ee, bristles 

 in the ureters where they open into the bladder, ff, the lymphatics. 



LV. Eclipses of Jupiter's First Satellite, the Eclipse of the Moon, and Occulta- 

 tion of Fixed Stars by the Moon. Observed at the Royal Observatory at Greevr- 

 wick, 1769. p. 399. 

 These observations may now be consulted in the general collection of all the 



Greenwich observations, which have since been published by Dr. Maskelyne, 



under the authority of the Royal Society. 



LP'I. Eclipses of Jupiter's First Satellite, with an Eighteen Inch Rejector of Mr. 

 Short's. Observed by Dr. Wilson at the Glasgow Observatory, p. 402. 



