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 thouand Kinds; and is, ditinctly peaking, no genuine Foil.

In order to the rightly undertanding what is meant by the calling any Subtance by either of the other Names, it may not be improper briefly to give their everal Ditinctions, o far as the general Uncertainty of the Foile Kingdom will permit:

1. Clays are Earths compoed of very fine Parts, mooth, heavy, not eaily mixing with Water; and when mixed, not readily ubiding in it; compact, vicid, and leaving a fatty Impreflion on the Tongue: oft while in the Stratum, and hardening by Fire into a kind of tony Texture.

2. Ochres are ponderous earthy Subtances, more fat than Chalk, and les o than Clay, readily diffuible in Water, and friable when dry, taining the Fingers in handling, and principally differing from the Boles, in that they are of a looer Texture.

3. Boles are ponderous earthy Subtances, more fat than Chalk or Marle, but les o than Clay; ponderous, of an atringent Tate, melting in the Mouth, taining the Fingers; and generally partaking more or les of the Nature of Iron; as indeed, in ome Degree, do mot, if not all, the other Earths, but the Boles generally more than any.

4. Marles are light friable Subtances, of a middle Nature between Clay and Chalk, not o fatty as the former, nor o dene as the latter, eaily diffuible in Water, and, when tated, dry, inipid, and adhering to the Tongue. 5. Chalks are earthy Subtances, dene, brittle, readily diffuible in Water, and quickly eparating themelves from it by Subidence, taining the Fingers in handling, and, in tating, ticking to the Tongue.

6. And Loams are earthy Bodies, of a dene, rough Texture, coniting of clayey or ochreous Matter, with arenaceous Particles of various Figures, Sizes, and Colours, immered in and intimately mixed with it.

Much more might be aid on this Occaion, were this a proper Place for it; but a general and uccint Account of what is meant by the general Names of Clays, &c. may be ufficient for what is intended in this Place; which is only to give omething of a determinate Idea of what is meant by the Words Chalk, Bole, &c. when there hall be Occaion hereafter to ay any of the Bodies decribed by this Author is of the Nature of one or other of thee Subtances. LXXXIV. But if Glas be made, as