A Description of the Stone- Quarry Near Maestrich; Communicated by an Observing Person, Conversant in That Country

the depth of the Moor evinceth, that it hath been so for divers hundreds of years, since that could not grow to that thickness it is of, in a few Ages. Of the Cause thereof he concludeth, that to have been the Muddiness of the constant Tydes, which flowing up Humber into Trent, left in time so much filth, as to obstruct the Currents of Idle, Done, and other Rivers, which thence flow'd back and overwhelm'd that flat Country. A Description Of the Stone Quarry near Maestrich; communicated by an Observing Person, conversant in that Country. There is an excellent Quarry, within Canon-shot of Maestrich, upon the very brink of the River Mase, lying in a Hill, where there are about 25 fathoms of Rock and Earth over head; the length of the Hill being of some miles extending along the River towards Liege, situate on the same River; and near Maestrich having in breadth, some \( \frac{1}{2} \) or \( \frac{3}{4} \) of a mile, but some more, farther off. This Quarry hath one Entry towards the River, where Carts can pass with great ease, and unload the Stones upon the brink of the River, the Quarry within lying parallel to the Horizon or level, (which is a great advantage) and elevated but very little above the River. This same Quarry, which hath, well nigh, undermined the whole Hill, affords one of the most surprizing Prospects, when well lighted with many Torches, that one can imagine. For, there are thousands of square Pillars in large level Walks, and those almost every where, above 20, and in some places, many more foot high, and all wrought with so much neatness and regularity, that one would think, it had been made rather with curious Workmanship for an under-ground Pallace, than that those Pillars and Galleries were made by Quarriers, that did it only for getting Stone to build above-ground. This Quarry serveth the People, that live thereabout; for a kind of impregnable Retreat, when Armies march that way. For, being acquainted with all the ways in it, they carry into it whatsoever they would have safe, as well their Horse and Cattle, as their Moveable furniture, till the danger be over; there there being so vast a deal of room, that 40000 People may shelter themselves in it. And he that would attempt to seek them out in this vast Wilderness of Walks and Pillars, without an expert Guide, would not only be in hazard of loosing his way, but of being knock't in the head at the Corner of every Pillar, where people lurking in the dark with their Carabins and Fowling pieces, would have fair opportunity to shoot them by the light of their own Torches. In this vast Grotto 'tis remarkable, that there is but little Rubbish: which shews both the goodness of the Stone, and the carefulness of the Workmen. And in divers places there are little Pools of Water, perhaps made on purpose for Beasts to drink, and to serve for other uses in time of need: For in no place almost are there any Droppings to be seen; nor are the Walks at all wet under-foot; only it seems, that Rain gets in by the Air-shafts, which, for saving of labour, and perhaps too, to make these Pools, are let down from such places commonly, as are the Pools thereabout; and so the Rain, that falls on the higher grounds, does easily find the way thither. An Account of some Books. I. TRACTS written by the Honourable Robert Boyle, of a Discovery of the Admirable RAREFACTION of the AIR (even without Heat:) New Observations about the DURATION of the SPRING of the AIR: New Experiments touching the CONDENSATION of the Air by meer COLD; and its COMPRES- SION without Mechanical Engins: And the admirably DIFFERING EXTENSION of the same Quantity of Air rarified and compressed. London, for H. Herringman, 1670. in 4°. The main drift of these Excellent Tracts is, to invite the Curious to observe the stupendious Mutability of the Air, as to Rarity and Density, whereby the same Quantity of Air, being sometimes compres'd, sometimes dilated, may change its Dimensions to a degree, that seems almost to transcend the power of Nature and Art, and might be look't upon as incredible, if it were abruptly and nakedly proposed, or by a person of only common skill in these matters.