[ii8 9] 
entSj which be had before told me, would afford any 
hint, ot the caufe of lo odd an Effed; alike to which 
in kind, tho' not in degree, I had many years before 
devifed, and fuccefsfuUy pradifed, the way of pro- 
-ducing. 
The Veffel being come, tho' the hafty tranfporta- 
tion of it feemd to have fufficiently difturbed it, there 
did appear manifeft figns of fuch a motion, as the En- 
gineer had afcribed to it; and therefore he being wil- 
ling to leave it with me, I caiisd it to be fet afide iu 
Sa Laboratory, where fome Furnaces kept the Air con- 
ftantly warm, and did there and elfewhere, at diftant 
times, look heedfuUy upon it, now and then difplac- 
ing, or quite taking off, fome of the thick Scum, that 
too much covered the furface of it ; and by this means _ 
I had the opportunity to take notice of feveral Phivfia- 
^^;2/^, whereof thefe are the chief. 
Firft I obferv'd, that the motion of this Liquor was 
not only brisk, but very various 5 lo that having 
loofen'd fome imall portions of the Scum from the 
reft, one of them would be carryed towards the Right 
hand for inftance, and another towards the left, at 
the fame time.— 2. Where the Liquor firft came out 
from under the Scum, it leem'd to move the moft 
briskly, flowing alraoft like a ftrenm, whole motion 
upwards had been check'd, and as it were reverberat- 
ed, by that incumbent obffacle.— j. Several motions 
in this Liquor were the more eafy to be obferv'd y 
becaule tho' it were dark, yet it was not uniform, con- 
filling in part of Oyly and Bituminous Ingredients^, 
which tho* they feem'd to have but one common 6"/^- 
perfictes with the reft of the Liquor, yet by their co- 
lours and power ofvigoroully refleciiing the light, they 
wereeafily enough diitinguiflhable from the reft. And I of- 
ten obfervedy that fome of thele uad:iou5 portions of the 
matter.emerging to the lurface of theLiquor,tho' perhaps 
H h h a at 
