pofitiop} In regard that the matter qf 
the Marcafite is joyned to all the plane 
Cubes, otherwife than we have faid it 
falls out in Ghryftals; yVhich the Uni-* 
formity of all furfaces manifeftly fhews 
in the Cubes I my felf haye digged out of 
Stones ; all the planes of which had 
ftreaks parallel to two li4es, in fuch a 
manner that in the oppofite planes the 
ftreaks vyent in the fame dul^us the fame 
Way, but the planes next to each other 
had ftreaks going different ways. From 
the duiim of the ftreaks it follows, that 
the Ambient fluid was determined by a 
three-fold motion about every Cube, 
whereof one was perpendicular to theHo- 
rizon^ the other two parallel to it, but 
perpendicular to each other. Kor will 
it be difficult to explicate the manner of 
this three-Ibid motion: for, vyhilft the 
fluid endeavours to recede from the Cen¬ 
ter of the Earth, that diredt motion is 
hinder'd by the of the Cube 5 
whereby it happens tnat the faid fluid is 
turned tovyafds the narrower fides, in 
regard that the imfettts of the afcending 
fluid through the larger fides is ftroh- 
|er, and therefore perinits no paffage 
