earth than had been suspected by geologists. Werner confines it almost entirely to the clay-slate formation; and Von Buch conjectures that it may be the oldest rock with which we are acquainted. Both of these statements are incorrect; for it is found associated with nearly all the Primitive Rocks of authors; also with those of the Transition class, and is even included in Sandstone; and as there is no satisfactory evidence of one primitive rock being older than another, the whole class appearing to be a simultaneous crystallization, there is no reason why quartz-rock, which occurs along with all the others, should be viewed as the oldest *.

Imbedded Quartz-Rock.

Quartz-rock occurs in masses, in rocks of different kinds. These imbedded masses, according to their magnitude, form hillocks, hills, or ranges of hills. The strata around these masses have the same positions as are observed with imbedded masses of granite; and the lines of junction of the quartz with the adjacent strata, exhibit intermixtures, transitions, and veins, as in granite.

Quartz-Rock in Beds.

The tabular masses or beds of quartz-rock are sometimes so thick and extensive as to form whole hills; and their lines of junction exhibit the usual appearance of veins, intermixtures and transitions.

Quartz-Rock in Veins.

Veins of this rock are very frequently met with in some districts, and these are occasionally several fathoms wide, and of considerable extent.

Rocks in which Quartz-Rock occurs.

Quartz-rock, like granite, sometimes occurs in large imbedded masses in syenite, and also in masses and veins in

gra

• The arrangements that occur in Galloway, on the east coast of Sutherland and Caithness, on the sides of Loch Ness, and in several neighbouring districts, on the west coast of Ross-shire, Inverness-shire, and in several of the Hebrides, seem to lead to the conclusion, that the transition rocks, and certain kinds of red sandstone, belong to the same grand division as the primitive rocks. We intend to give a full enumeration of the facts illustrative of this view in a future Number.

nite. It is a common rock, in beds, in some gneiss and micaslate districts; and frequently, it is distributed very abundantly through hills and mountains of clay-slate, in the form of beds, imbedded masses, and veins. It sometimes appears in greywacke districts, and great beds of it are observed alternating with red sandstone.

III.-Geognostical Relations of Red Sandstone.

In general all the different kinds of sandstone have been considered as entirely unconnected with any of the primitive or transition rocks, and strictly confined to the secondary class. This restriction, however, is not consistent with our present knowledge of the geognostical distribution of this rock, and it is now known that some sandstones are connected with rocks, considered by authors as members of the transition and primitive classes.

Red Sandstone in Beds.

This rock occurs in beds of very various magnitudes. These at their line of junction with the bounding rocks, shew intermixtures, transitions, and veins or shoots from the upper and lower side, and from their extremities.

Red Sandstone in Imbedded Masses.

Red sandstone also occasionally occurs in large imbedded masses, like those of granite in syenite, or of quartz-rock in gneiss, in strata of different kinds. Small veins shoot from the sandstone into the bounding rock, and frequently intermixtures and transitions are to be observed, with the neighbouring strata.

Rocks in which Red Sandstone occurs.

Red sandstone occurs, in imbedded masses and beds, in granite, porphyry, granular foliated limestone, clay-slate, and gneiss.

5.

It thus appears that granite, quartz-rock, and red sandstone, exhibit the same relations on the great scale, as they do in the smaller masses mentioned in the 3d section; and hence it follows, that these rocks are chemical deposites, and of simultaneous formation with the various strata in which they are contained.

ART. XXI.—Account of an Improved Hygrometer. By JOHN LIVINGSTONE, M. D. of Canton *.

HAVING

AVING observed in the process of making ice, that the power of the sulphuric acid was remarkably equable from the point of its highest concentration till it had formed ice twelve or fifteen times, I was led to entertain the expectation, that it might be found to act with sufficient uniformity in a more advanced state of saturation. As the trials which I made were highly satisfactory, I shall briefly describe my method of constructing a Hygrometer upon this principle.

In the scales commonly used as a hydrostatic balance, I placed a small porcelain dish three inches in diameter, containing 21 grains of very pure sulphuric acid, of the specific gravity 1.845, and 29 grains of distilled water. Having exposed it to the greatest degree of artificial moisture, I found that it gained 50 grains in 24 hours. When it was afterwards placed for one night in a platina dish over concentrated sulphuric acid, and under the receiver of the ice machine, its weight was reduced to 50 grains without exhausting any of the air.

Half a grain made the edge of the scale of this balance describe an arch, exceeding an inch both above and below the level. This space I divided into ten equal parts both above and below, or the grain into 20 parts, which, multiplied by the 50 grains, gave me a scale of 1000.

I have used this instrument, inclosed in a glass cover, but sufficiently open below to admit the air frecly, for nearly six months; and, from a careful comparison with other hygrometers, I am persuaded it is more accurate than any now in use, though, in its present state, it is less sensible than Kater's.

It has frequently approached in the natural atmosphere, within a few divisions of the point of greatest humidity, and also within 143 of that of greatest dryness. Considering this range,

We have been favoured with this extract of a letter from Dr Livingstone, by a gentleman who has seen the instrument which it describes. From the same quarter we are led to expect a detailed account of Dr Livingstone's meteorological observations in China, which we have reason to believe will prove in the highest degree interesting.-ED.

however, as unnecessarily extensive, I have made another with 2.1 grains of acid and 2.9 of water, and exposed this mixture in a common flat watch-glass. The scale was only 100, but by means of a Vernier it may be divided into 1000.

This instrument, which is fully as sensible as Kater's Hygrometer, pointed to 950 (or the mixture weighed 91 grains) at Macao, on the 7th February 1817, during the prevalence of a remarkably thick fog. It continued so till bed-time; but next morning, at seven o'clock, the wind having changed in the course of the night from S. W. to N. E. it had lost 4 grains, or had fallen to 100. This is the most remarkable change I have ever witnessed even in China.

I could wish to have scales made of glass as flat as possible, with a small rim perforated with three holes, to be suspended to the beam by means of platina wires, and to have a very light glass-cover suspended by the same wires, within a very small distance of the rim. To the other end of the beam a moveable weight may be appended to mark the larger divisions; the beam may be lengthened to describe any arch of a circle, and consequently the divisions may be as minute as can be wished. Dust will thus be excluded, and should the objection of spontaneous decomposition be considered to have any weight, or in case of exposure to alkaline fumes, the mixture may be renewed with scarcely any trouble.

ART. XXII.-On the Temporary Residences of the Greenlanders during the Winter Season, and on the Population of North and South Greenland, By Sir CHARLES GIESECKE', Professor of Mineralogy to the Dublin Society, M. W. S. &c, Communicated by the Author,

THE Greenlanders being a migrating people, transfer very often their abodes for the winter season from one place to another. Their houses are generally built near the shores on small islands, or at the mouths of the firths. They cannot subsist in the interior of them, as the sea is frozen there very early in the autumn. The following places were inhabited during the years from 1810 to 1813.

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Sir Charles Giesecké on the

I. JULIANAS-HAAB District.-In the South of Greenland, that is in the 60th degree, or the most southern district of Julianas-haab, round Cape Farewell, are inhabited,

1. Alluk, (that is, the soles,) two small islands presenting the shape of the soles of the foot.

2. Kippingujak, an island to the south of Alluk.

3. Pysursoak, a small bay to the north of Staatenhuck.

4. Nettingiak, on the continent, eastward from Cape Farewell.

5. Nennortelik, (that is, Bear-land,) an island eastward from Cape Farewell.

6. Tessermint, a large firth to the north of Cape Farewell, formerly inhabited by the old Norwegians. At the mouth of this frith, there are several Greenland houses, sixty-four miles south from the colony of Julianas-haab, in the 60th degree.

7. Kognamint, to the south of Julianas-haab, on the continent. 8. Innersutalik, an island forty miles southward from Julianas-haab.

9. Agluitsock, on the continent, thirty miles southward from the colony.

10. Sardlok, an island sixteen miles southward from the colony. 11. Omenalik, twelve miles to the south of the colony. 13. Upernaviarsuk, sixteen miles towards the east of the colony. 14. Itiblik, twenty miles towards the east of the colony. At the colony of Julianas-haab, only natives are employed in the service of the trade, who live in Greenland houses.

Between the 61st and 62d degrees are inhabited,

15. Ikertongoak, an island eight miles towards the west, at the mouth of the firth called Kakortok.

16. Narksak, in the vicinity of the continental ice, twenty miles northward from the colony.

17. Krimatuluitsanik, an island forty miles northward from Julianas-haab.

18. Okaitsermint and Kikerteitsiak, forty-four miles from the colony. Here ends the district called Julianas-haab. It is inhabited by 1762 natives, viz. 754 males and 1008 females.

II. FREDERICKS-HAAB District extends from the Nunarsoi Island to the Ice-blink, about of a degree to the north of Fredericks-haab. Of the southern part of the district are inhabited,