VOL. L.l PHILOSOPHICAL TRANSACTIONS. 2J5 



the internal side the pores of the pericardium appeared so large, that one might 

 have insinuated the head of a middling pin into them. They had been described ' 

 by some anatomists, who had met with cases somewhat similar to this, but with- 

 out such universal adhesions ; and they had been supposed to have been glands. 

 The same pores likewise appeared on the heart ; which in his opinion were no- 

 thing but the extremities of the exhaling vessels. In removing the heart he 

 found the dorsal, and other lymphatic glands above the lungs, quite large, indu- 

 rated, and of a dark greyish colour. Nothing remarkable appeared in the lungs ; 

 only that the portion of the pleura, which invests the lungs, and is generally 

 thin, was here thick and rough ; and through a glass it appeared as if covered 

 with grains of sand ; and might in several places have been easily torn from the 

 lungs. 



The aorta was pretty large ; and m that part of it which runs on the tenth 

 dorsal vertebra, he found a cystis, as large as an olive, full of pus ; and lower 

 down, immediately before that vessel perforates the diaphragm, he found an- 

 other something less, full of matter likewise ; both which portions he had by 

 him. That portion of the aorta, where the cistis appeared, was rather thicker 

 than the other, and osseous. In opening the cranium, he found in that part of 

 the cerebrum, which lay over the cerebellum, a table spoonful of pus, of a green- 

 ish colour , and examining it through a glass, there was an appearance of ani- 

 malcula in it. 



LXXIIL On the best form of Geographical Maps. By the Rev. Patrick Mur- 

 doch, M.j4., F.R.S. p. 553. 



When any portion of the earth's surface is projected on a plane, or transferred 

 to it by any method of description, the real dimensions, and often the figure and 

 position of countries, are altered and misrepresented. In the common projec- 

 tion of the two hemispheres, the meridians and parallels of latitude intersect at 

 right angles, as on the globe, but the linear distances are every where dimi- 

 nished, excepting only at the extremity of the projection : at the centre they are 

 but half their just quantity, and thence the superficial dimensions but a 4th part: 

 and in less general maps this inconvenience will always in some degree attend the 

 stereographic projection. The orthographic, by parallel lines, would be still less 

 exact, those lines falling altogether oblique on the extreme parts of the hemi- 

 sphere. It is useful however in describing the circum polar regions : and the 

 rules of both projections, for their elegance, as well as for their uses in astro- 

 nomy, ought to be retained and carefully studied. As to Wright's, or Merca- 

 tor's nautical chart, it does not here fall under our consideration : it is perfect in 

 its kind ; and will always be reckoned among the chief inventions of the last 

 age. If it has been misunderstood or misapplied by geographers, they only are 



