50 «Mr. Harcwerr’s Odfrvations on Bituminous Subflances, 
the'letter:B,has been found during ‘the laft three years.in a rivulet 
which runs ‘at the bafe-of Mamtor, from Weft to Eaft, at a fmall. 
diftance from Odin mine.—The varieties of it, in my poffeflion, are 
as follow : Di 
vei ifs SPECIES, THE “SECOND. 
B,. No.:1. 
Evastic bitumen, which, ‘recently cut, exactly refembles fine 
clofe cork in colour’and texture, but, by the air, in a few days it 
becomes of a pale reddifh brown.—This forms a thin coat, which 
completely covets a mats of elaftic bitumen, which is foft,and. ofa a 
brownith olive colour, like A, No. 9. ‘tous 
B, No. 2. 
The fame, excepting that the coat or’ cruft is much eid 
-B, No. 3.- 
The fame, but the coating is thicker than that of No. Ma and the 
brownifh olive-coloured bitumen much lefs in quantity. © ws iiiew 
JB, No. 4). 
- 'The fame, excepting that the greater part of the mafs-refembles 
cork; fo that only’a very fmallinucleusi:ofi thei brown (bitumen 
remains *. aiwRert bas wolos 
-B, No. 5%. 
» The fame, excepting that the hapaelé which is coated, 1 isin. the 
ftate of afphattumiaq! sis) ni oteigmoo sis muiladqis io ewietwsd 
The fpecific gravity of this FAL ab BOMS8ie8 1 siioog! off 
~* One, of the fpecimens in my BeSefhigm sSosler te B No, 46 | Weighs between 
bs and 14 pounds. B. No.6 
» No. 6. 
