644 PHILOSOPHICAL TRANSACTIONS. [aNNO 17 11. 



called ActaBon, by such authors as mention it; but the bare inspection of it 

 shows, that it is a representation of the fable, which says, that a person having 

 found fault with Venus, she, to be revenged of him, engaged her son Cupid to 

 make him fall in love with a monster. 



It was first discovered about 40 years ago, on digging the cellar, at about a 

 yard and half under the common present surface of the earth. What extent 

 the whole pavement was of, is not known ; but this figure, which, by order of 

 the master of the house, was preserved, is an octagon, surrounded by a list, as 

 you see in part represented in the corners of the drawing, fig. 2, pi. 17. With- 

 out this, though not here represented, is a twist or wreath of various colours ; 

 and round that, is a second like the former. These two lists, with the wreath 

 between them, are 64- inches broad. The perpendicular and transverse dia- 

 meters of the area, are just a yard ; but the others, from corner to corner, 

 are a yard, 2^- inches. The man's figure, from head to foot, is 2 feet 4-» 

 inches. Cupid seems to be 2 feet; but his feet, as well as the bottom of 

 the monster, are wanting, the tessellae representing them being gone. The 

 whole area of the figure, which is here left blank, ought to be filled up with 

 white tessellae, in like manner as is seen in some intervals of the figures. 



An Account of the Repetition of Dr. Hook's Experiment^ concerning two Liquors 

 which, when mixed together possess less space, than when separate: with another 

 Experiment confirming the same. By Mr. F. Hauksbee, F. R. S. N° 331, 

 p. 325. 



The experiment related by the late Dr. Hook, in one of his papers delivered 

 to me by Mr. Waller, is concerning two liquors, which when mixed together, 

 possess less space than when separate ; which he calls a penetration of dimen- 

 sions : and further he adds, that this penetration is the cause of heat, of fire, 

 of flame, of the power of heat, fire, and gunpowder, and several other sur- 

 prising phaenomena in nature. On which account 1 thought it very worthy an 

 examination, by a repetition of the same. 



Accordingly I procured a bolt-head, such as Dr. Hook describes, with a long 

 small stem, which I filled nearly full of common water. The stem was marked 

 into several divisions, on a piece of paper pasted on it; by which means I 

 nicely observed the height of the surface of the water. Then pouring as much 

 of it out as filled a certain measure, which being thrown away, I filled the same 

 measure, as nicely as possible, to the same height, with strong oil of vitriol ; 

 which I returned into the bolt-head, instead of so much water taken out. On 

 the mixing of these liquors ensued a pretty strong ebullition, and abundance of 

 airy particles were visibly extricated, and the surface was not so high in the stem 



