es, by surer proofs than the Testimony of
our Touch?

3. Whether they ever meet with places and Stones actually very hot, as
_Matthesius_ relates? And whether that spring not from the quenching of
_Marchasites_?

4. Whether they find in the Mines any Mineral Gelly, such as the _German_
Naturalists call _Ghur_? And whether in process of time it will harden into
a metal, or Mineral Concretion?

5. What are the Laws, Constitutions, and Customs, _Oeconomical_,
_Political_, _Ethical_, that are receiv'd and practis'd among the Mine-men?

6. Whether the Diggers do ever really meet with any subterraneous _Demons_;
and if they do, in what shape and manner they appear; what they portend;
and what they do, &c?

7. Whether they observe in the Trees and other Plants, growing over or neer
the Mine, not only, (as hath been already intimated) that the Leaves are
any whit gilded or silver'd by the ascending Mineral Exhalations, but also,
that the Trees or other Plants are more solid and ponderous? And if they
have not also some discernable Metalline or Mineral Concretes, to be met
within the small Cavities and Pores of their substance?

8. Whether there be not Springs, and also greater Streams of Water neer the
Mine, that rise, and run their whole course under ground, without ever
appearing above it?

9. Whether the Subterraneous Springs do rise with any wind or determinate
change of weather?

10. How much heavier the _Atmosphere_ is at the bottom of the Mine, than at
the top? And whether Damps considerably increase the weight of it?

11. Whether they find any strange substances in the Mines, as Vessels,
Anchors, Fishes inclos'd in Sparr or Metal, &c.? {344}

* * * * *

__Promiscuous Inquiries_, chiefly about _Cold_, formerly sent and
recommended to Monsieur _Heuelius_; together with his Answer return'd to
some of them._

A considerable piece of the grand Design of the Modern _Experimental_
Philosophers being, to procure and accumulate Materials for a good Natural
History, whence to raise in progress of time a solid Structure of
Philosophy; all possible Endevours are used in _England_, to send abroad
and recommend to as many of Forreign parts, as there is opportunity,
_Directions_ for searching into the Operations of Nature, and for observing
what occurs therein, aswell as in Mechanical operations and practices.

Several Heads of that kind have been already publish'd for this purpose in
sev