262 Dr Brewster's Description of GmeUnite, 



June 24>. Since the 22d, we have been coming up the river 

 with the tide, the wind being either very light or contrary. 

 About noon to-day we reached Gravesend, and landed. 



London, July 16. I have just ascertained the specific gra- 

 vities of the different specimens of sea- water which I took up 

 between the Cape and England. There appeared to be no 

 sensible loss by evaporation. Each bottle was quite sweet and 

 unaltered. I used the delicate balance of the ftoyal Institu- 

 tion, and a bottle with a long neck, weighing 778 grains, and 

 of the temperature of 63°, holding 970.3 grains of distilled 

 water. On the sides of the glass stople there was a fine groove. 

 The temperature of the different specimens of sea-water was 

 the same as that of distilled water, viz. 63°. Most of the ex- 

 periments were twice repeated. 



No. Lat. Long. Specific Gravity. 



1 30° 6'S. ]1°42'E. 102667 



2 26 55 7 34 102671 



3 6 N. 19 17 W. 102067 



4 9 5 25 8 102671 



5 12 6 28 28 102671 



6 15 56 32 38 102762 



7 18 15 34 6 102762 



8 20 55 35 49 102762 



9 23 27 37 8 102823 



10 28 1 37 57 102823 



11 31 8 38 27 102762 



12 34 8 37 57 102823 



13 42 10 30 86 102742 



14 44 51 26 37 102721 



15 47 5 14 12 102721 



16 49 3 8 1 102721 



17 Off Dover £ mile. — 102648 



Art. XIV. — Description of GmeUnite, a New Mineral Spe- 

 cies. By David Brewster, LL. D. F. R. S. Lond. and 

 Sec. R. S. Edin. 



Among the minerals of Monte Somma, the late Mr Thom- 

 son of Cambridge discovered some crystals of a flesh-red col- 

 our, to which he gave the name of SarcoUte. The Abbe 

 Hauy, to whom he sent some fragments of these crystals, 



