VOL. VI.] PHILOSOPHICAL TRANSACTIONS. 5^7 



other accident; for it is seldom found on the open surface of the ^ound, unless 

 brought thither by an accident since the flood, especially in cultivated places ; 

 seeing that the corruption of vegetables and other creatures have in the long 

 tract of time produced a new surface, heightened in some places above a foot, 

 in others more or less. 



When all these ways have been attempted for finding shoad, if we find any, 

 it makes us proceed with the greater confidence, having an assurance of a 

 load; but otherwise we must go by guess. And here is all the difference as 

 yet between finding and not finding shoad. For in the next place we sink 

 down about the foot or bottom of the hill an essay hatch, an orifice made for 

 the search of a vein about six feet long and four broad, as deep as the shelf. 

 And it is observable, they are always to be as deep as the shelf, for this reason, 

 that otherwise you may come short of the shoad ; but if we meet with none 

 before, or when we come to the shelf or fast country, there is none to be ex- 

 pected ; yet sometimes the shoad is washed away clean, when you come within 

 two or three feet from the load, and then the load is a foot or two further up 

 in the hill. If we find any shoad in this first essay hatch, our certainty is 

 either increased if any shoad were found before, or begun. Neither does it 

 add a little to make a right conjecture, how high up the hill, or far off, the 

 load, string, or bonny is, carefully to mark how deep from the surface of the 

 earth our shoad lies : for this is held an infallible rule, that the nigher the 

 shoad lies to the shelf, the nigher the load is at hand, et vice versa. 



Although we find no shoad in this first hatch, having found some before by 

 the ways before-mentioned, or having found none, we are not as yet altoge- 

 ther discouraged ; but ascend commonly about 12 fathoms, and sink a second 

 hatch as the former : And in case none appear in this, we go then as many 

 fathoms on each hand at the same height, and sink there as before, and so 

 ascend proportionably with three or more hatches, as it were in breast, till we 

 come to the top of the hill, and if we find none in any of these hatches, then 

 farewell to that hill. 



But if we find any shoad in any of these hatches, we keep our ascending 

 hatches in a direct line ; and as we draw nearer the load, the deeper the shoad 

 is from the surface, but nearer the shelf; as suppose it be seven feet deep, 

 and but half from the shelf, then we presently conclude the load to be within 

 a fathom or two of us, and so we lessen our first proportion accordingly, as of 

 that of 12 fathoms to 6, 4, 2, 1 ; as our conjecture guides us. 



Sometimes we Overshoot a load, that is, get the upper side of it, and so we 

 lose it ; for which we have another good rule, viz. that finding shoad lying 

 near the shelf in this hatch, and' finding none in the next ascending, we have 



