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GLISCHROMICTHES.

2 . GlifchromiSihes pallidifime saves ens .

Pale-yellow GlifchromiSihes.

This is a dense, firm, and compact Loam ; while in the stratum it is moderatelymoist, and something tough or viscid; it cuts very easily and evenly thro’ with thespade, and leaves a smooth, but not glossy surface behind it; when dry, it is of a firm,hard texture, and very pale-yellow colour, spangled with a fine sebaceous Talc, mo-derately heavy, and of a tolerably smooth, but hard surface ; it scarce at all adheres tothe tongue ; is dry, and somewhat harsh to the touch ; is not easily broken betweenthe fingers, nor at all stains the hands ; it melts but slowly in the mouth, and is not socoarse as many others between the teeth ; thrown into water it makes very little ebul-lition, or hisling, but after a few minutes falls into a loose powder.

View’d by the Microscope, it appears of a loose spungy texture, and compos’d of asmall whitish sand, held together by a pale-yellow clay.

It makes no effervescence with Aqua Fortis.

In the fire it acquires a fine florid red, without any considerable hardness.

It is dug in most parts of England, and makes a fine red brick.

3 . GlifchromiSihesflavo-fufca.

Yellowtjh-brown GlifchromiSihes,

This is the common brick earth of London, and many other parts of the kingdom;while in the stratum it is very firm, tough, and viscid, cuts evenly and easily thro’ withthe spade, and leaves a smooth, even, and somewhat glosiy surface behind it; whendry, it is of a dusky, yellowish brown, of a close, compact and firm texture, and veryheavy ; it is of a tolerably smooth and even surface, adheres not at all to the tongue,is somewhat smooth to the touch, is not easily broken between the fingers, nor at allstains the hands; it melts but slowly in the mouth, and is very coarse and grittybetween the teeth; thrown into water it makes a slight ebullition and hisling, andafter some time crumbles into small pieces, and from them moulders into powder.

-Examin’d by the Microscope, it appears of a loose texture, and compos’d of a whiteand a yellowish sand, held together by a considerable quantity of a fine brown clay.

It makes no effervescence with Aqua Fortis.

It burns to a good red, with great hardness.

It is dug in most parts of England, and makes very fine brick, but about London itis seldom us’d pure, but mix’d with ashes, dirt out of the streets, &c.

4 . GlifchromiSihes fufeo-rubefeens .

Reddifh-brown GlifchromiSihes .

This is a common brick earth in some counties; while in the stratum it is of a firmand somewhat viscid texture, cuts evenly with the spade, and leaves a smooth surfacebehind it; when dry it is of a firm texture, very hard, of a pale and somewhat reddishbrown, and very heavy; it is of a rough unequal surface, adheres slightly to the tongue,is hard, dry, and harsh to the touch, does not break easily between the fingers, nor atall stain the hands^ it melts slowly and disagreeably in the mouth ; thrown into waterit makes very little ebullition or hisling, and after some time falls into powder.

Examin’d by the Microscope, it appears of a loose texture, and compos’d of a coarse,whitish Sand, held together by a reddish brown clay.

It makes no effervescence with Aqua Fortis.

It burns to a fine red, but with no great hardness.

It is dug in Staffordshire, Buckinghamshire, and many other counties, and us’d Mbrick-making, but it makes but a very coarse soft kind ; it generally lies near the sur-face, and in some places shews itself in the roads.

SERIES