[ 399 ] 
more particularly, pleafe to communicate, and it 
(hall be done with the greateft pleafure by, 
S I R, 
Your moft obedient and 
obliged humble fervant, 
Wm. Bullock, 
Francis Mafon, overfeer, fays, That he fat in a 
little room, which he ufes to write in: it Rands 
about forty yards from the mouth of one of the en- 
gine fhafts. He felt one Ihock, which very fenfibly ' 
raifed him up in his chair, and caufed feveral pieces ■ 
of lime or plaifter to drop from the (ides of the- 
room : the roof of it was fo violently fhook, that he 
imagined nothing lefs than the engine (haft was run 
ini whereupon he immediately went out to fee, and,, 
contrary to his expectation, found the fhaft open,, 
and all things about the fpot in their proper order* 
Upon inquiry, I was informed by the aforefaid 
Francis Mafon, that in a field about 300 yards from^ 
the mines, there had happened a chafm or cleft on- 
the furface of the earth, which was fuppofed to be 
made at the fame time he felt the fhock, for the fol- - 
lowing reafon : It lies clofe by a-road, which he ufes 
daily to and from the mines i in the morning when • 
he came, there was nothing uncommon to be feen, 
but on his return at evening heobferVed a cleft about 
one foot deep, and fix inches in diameter j its con- 
tinuation from one end to -the other, . was near 150^ 
yards^^ 
