68 MEM O IR S of the 
inoillure fwells tliem, and lightning may difpofe tliem to emit 
their psirticular fcent, To alluring to Iwine, for lome of the ancients 
called them Ceraunia. 
Dr. Hatton oblerved fibres iiTuing out of feme of thefe \tuhera^ 
which lay fpit-deep under ground, io that they may be plants 
fui generis^ and their furrowed 'Papillce analogous to, if not 
iecd-vellels ; for feveral vegetables bear their leed near the root, 
as the trifoUum fiibterraneum tricoccum reticulatwn^ flofculis 
lon^is albis^ moft of the ^racbidnaSy and fome other pulfe, 
which flower above, but feed under ground 5 as to the truffles 
lying ^o deep, they have that in common with many roots that 
ihoot up ftaiks above the earth ^ to inftance only in the Terrte 
GlandeSy in Efiglip^ peafe-earth-nuts, which are dug up and 
eaten by the poor people 5 the roots of our "Bulhocaftamim^ of the 
umbelliferous kind, commonly called keppernuts, pignuts, and 
gernuts in the north , lie very deep, and fatten hogs, ^which are 
very greedy of them. 
An Earthquake in Sicily; hy Mr. Martin Hartop. Phil. Tranf. 
lv!° 202. p. 827. 
IT fcems highly probable, that thefe tremblings of the earth 
proceed from the fame inflammable matter, which, finding a 
way at other times thro' Mongibello^ breaks out fo furioufly in 
fire and imoke *. The eruptions of thele mountains are of two 
forts 3 the one not fo violent, as very much to difturb the adja- 
cent country ; and this happens once in two or three months, and 
lafls three or four days ; the other is more furious, and of longer 
continuance, and is obferved at Naples to happen to mount 
VefuvitiS once in about 80 years 3 that in 1552 was fo very vio- 
lent, that it threw rocks three miles into the air 3 now from the 
burning or not burning of this hill, Naples concludes its lafety or 
danger from earthquakes 3 for doubtleis the matter is continually 
burning under the mountain 3 and thofe vaft clouds of fmoke, 
which daily iffue out at the top, if the cavity happen by any 
rock, or inward alteration to be flopped, muft deviate thro' 
other paffages under gro-und, heaping up there continual magazines 
for a future calamity: Now this ccmbuilible matter feems to be 
nothing other but nitre, mixed with fome other minerals and liil- 
phur3 for he that has fecn the metho^ of making of tartar by 
deflagration, where an equal quantity of pulverized nitre is 
mixed, has an exadl: type of thck- burning hills 3 for after each 
ipnonful that is put into the burning crucible, there arifes firfl: a 
black thick fmoke, after which the fired mineral boils up, as if it 
would run over the top of the crucible. ' The 
