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The height above their base, and above the level of the sea?

The length, breadth, and general form, of a horizontal section passing through the base, or the ground plan; and the points of the compass between which the long diameter lies?

The degree of declivity on every side with regard to the circumjacent plain?

Do they present on any side abrupt craggy faces; and to what points of the compass are these opposed?

Do these precipices extend to the foot of the mountain, or are there at their bottom sloping banks of loose fragments?

Is the surface smooth or rugged? dry or marshy? To what height does vegetation ascend, and what are the prevailing plants in different parts of the ascent?

The springs, streams, lakes, hollows, gullies, caverns?

Whether any loose blocks of stone are found on the surface different from those of which the mountain is composed?

In addition to the preceding inquiries

If in a Group,

Are the component mountains of nearly the same height? Which are the highest, the central

or external ones?

If in a Chain,

The outline of the chain?

Its highest point?

Its length?

extended between what points of the compass?

Whether any lateral ridges proceed from the same chain?

II. CONCERNING VALLIES.

Their geographical boundaries? Their length, breadth, depth? Are they occasionally dilated and contracted, or do their sides preserve any uniform parallelism?

Is the bottom or floor even or rugged?-nearly level or much inclined? If inclined, whether regularly or interruptedly, and in what direction?

Are the slopes that form their sides smooth and gentle, or rugged and precipitous ?

Do the opposite sides consist of the same kind of rock, and do they correspond in the inclination of their beds or strata?

Are there on their sides depositions of water-worn and rounded pebbles, either loose or compacted, and to what height do they reach?

Are the detached fragments, by which the bottom is overspread, angular or rounded? of the same species of rock as composes the sides of the valley, or different?

Of what description is the solid rock or base upon which these rest? Are they open or closed at one or both extremities?

Do any subordinate lateral valleys open into the main one, and what remarkable circumstances occur at their junction?

Do streams rise in, or flow through them, and in what direction?

III. CONCERNING PLAINS.

Their shape and extent-with the nature, height, and general appearance, of the hills or mountains by which they may be bounded?

The degree and direction of their inclination or slope?

The nature and character of the different soils by which they are co

Whether straight or curved, and vered?

Whether

Whether dry or abounding in springs and standing waters? If traversed by streams, in what direction do the flow?

Are the beds of rounded pebbles (if such occur) composed of minerals similar to those which form the surrounding mountains?

Have any opportunities presented themselves, in sinking shafts or wells, cutting canals, excavating docks and quarries, and digging foundations, of examining the subjacent strata; and what are the results of such observations?

IV. CONCERNING RIVERS.

Their source, their mouth? The direction and length of their course, and whether those are the came now as formerly?

ty?

Their breadth, depth, and rapidi

What is the rate of their descent or fall? is it uniform or interrupted? The amount of their periodical in

crease or decrease?

The colour, temperature, and other properties, of the water?

Whether any part of their course is subterranean >

Do they run in the same direction as the strata, or cross them, and at what angle?

The nature of the bed, whether rock, mud, sand, or gravel?-Are the pebbles of the same rock as that of the adjacent country?

V. CONCERNING LAKES, STRINGS, AND WELLS.

1. Lakes.

The extent, depth, temperature, and other properties of the water? The periods and amount of their greatest annual increase and decrease? Whether supplied by spings or streams, and whether any streams flow out of them?

Of what is the basin composed?
Are there any appearances that in-

dicate the extent to have been formerly different from what it is at present;

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Are they separated from each other by thin bands of clay, or other extraneous substances? or slightly joined to one another? or firmly welded together?

When two rocks of different species come in contact, is any difference in colour, hardness, &c. observable between the adjacent surfaces, and other portions of the same rock?

When a rock terminates at the surface of the earth, are any fragments of it to be traced in the form of gravel, &c.? Does it re-appear after such interruption, and what is the nature of the intervening substance?

The form of their broken ends? Are any rocks observed to terminate constantly together, and what are they?

If Stratified,

Is the stratification distinct or indistinct?

What is the number and thickness of the strata, and the order of their position?

Do they alternate or recur at regular intervals?

Do they, whether straight or waved, preserve their parallelism throughout, or are they cuneiform, &c.?

When vertical, what points of the compass are opposed to their sides, and what to their edges?

What is the amount of their dip, or the angle which they form with the horizon, and is it the same throughout their whole extent ?

To what point of the compass do they decline?

Where several strata of the same species are incumbent on each other, do they differ in thickness or consolidation?

Where veins, dykes, or fissures, occur, are the strata depressed, elevated, contorted, or altered in any other way?

How far does the external form of the mountain correspond with the position of the strata?

thin distinct particles (such as mica), do these all lie in the same direction?

Note-Care must be taken in examining strata, not to be deceived by distance of perspective, or by mistaking fissures for stratification, and fallen strata for strata in their natural position; and it should be kept in mind, that, before the inclination of a stratum can be determined with certainty, it is necessary that it should be seen on two of its adjacent sides.

If. Unstratified,

Are they amorphous, columnar, or in globular concretions?

Do they split with the same ease in all directions, or have they what is called a grain?

Do they abound in fissures, and what is the direction and extent of these?

IX. CONCERNING THE MATERIALS OF
ROCKS.

Are they composed of one mineral substance, or of more? In the latter case, which has impressed the other?

Are they composed of parts cemented together, or adhering to each other without a cement?

Are they granular, slaty, porphyritic, amygdaloidal, or any compound of these? If Breccia, are the included nodules large or small, entire or broken, &c.?

Do they contain fragments of other rocks, and of what description? Sand? Shells? Corals? Vegetable impres sions, or any thing that appears to belong to a different formation?

Are there hollow nodules, and in what manner are they lined?

Is there any character, by which substances found in one stratum can be distinguished from similar substances found in another? or by which, what have been called primary strata, may be distinguished from secondary strata, and strata of transi tion?

What minerals are found to be ge

If the stratum contains broad and nerally concomitants of others?
June 1817.

How

"

How are the several species affect ed by the combined action of air and moisture? Where large fragments have been torn by torrents from known rocks, what is the progress of their decomposition, and is there any re-aggregation?

What are the characteristic forms of each species of rock-in mountains ?

——in detached blocks?

How are they affected by peat-moss lying on them?

What are the plants, the presence or absence of which indicates the nature of the soil?

By what local denominations are the different rocks distinguished, and to what economical purposes are they applied?

X. CONCERNING VEINS.

Are they of the same materials as the rock in which they occur, or of any contiguous rock?

What is their direction with regard to the points of the compass, and the inclination of the adjacent strata?

Are they vertical, horizontal, or inclined, and at what angle?

What are their several dimensions? Are they nearly of the same thickness at different depths? Do they terminate in a wedge, and this at the top or bottom of the vein ?

Is their longitudinal course straight

or curved ?

Is it of uniform breadth, or does it enlarge and diminish?

Do they ramify, and in what direction? Do the branches re-unite?

In what order are minerals arranged, of which the vein is composed? Are there any fragments of other rocks, any pebbles, any organic remains among them?

When a vein comes in contact with a different species of rock from that in which it was first observed, is the vein abruptly cut off, raised, depressed, turned aside, or are its materials altered ?

If a vein is cut off, or shifted by

the interposition of a stratum or mass of rock, does it re-appear or recover its direction on the other side of the interposed body?

Is it shifted or cut off without any apparent cause?

Are the neighbouring veins composed of the same materials?

Have veins, consisting of similar materials, the same direction?

What proportion do the several veins bear to the rock in which they are found?

Do they run parallel to each other Do they tend to a common centre? Do they cross each other, and what phenomena occur under these circumstances?

What is the nature of their floor, sides, and roof?

Do the veins seem to have produced any change on the adjacent part of the containing rock, as indu rating it, disturbing the regularity of its stratification, &c.?

Can they be traced to beds composed of the same materials as themselves?

XI. CONCERNING ORGANIC REMAINS.

To what class, and species, do they belong?

Do they conform to the direction of the strata in which they occur? Do particular shells, &c. affect particular strata ?

What change have they undergone? Are the vegetables compressed, carbonized, bitumenized, silicified, or penetrated with pyrites in whole or in part? Do the shells retain their enamel The bones their phosphoric acid? &c.

Do the shells, or other organic remains, appear perforated or wormeaten?

What is the nature of the rock or bed in which they are found?

Are the bones disposed in entire skeletons? are those of different animals mingled together?

Are the shells worn, broken, crash

ed.

ed, or thrown out of their natural poition? Are the different species conusedly intermixed?

Does this mixture extend not merely to speries and tribes, but even to classes? that is, are the remains of fish and sea-shell accompanied by those of land-animals and vegetables? Are any analogous living species now found, or known to have been formerly found, in their vicinity or elsewhere?

Among the various organic remains, can any traces be observed of the exstence of man ?"

Description of a New Smoke- Preventer. By Licut. - Gen. DIROM, of MOUNT ANNAN.

LAST year, I saw several new in

ventions in Liverpool for curing smoke, and brought two grates, of what appeared to me the simplest and best kind, to this place. They were tried in my dining-room and nursery, which smoked intolerably; the first wing to the vent having been carried, by mistake, into another, in building the attic storey; and the other, from being in a wing, was subject to a blow-down, which became much worse in consequence of the additional height of the body of the house. They lessened, but did not prevent the smoke; and in the diningroom we were much annoyed, even when there was no fire, by the back smoke from the other vent.

Having sent for William Elliot, an ingenious blacksmith in the village of Bridekirk, on this estate, to put up those grates, their failing of success induced me to employ him to make further experiments for curing the smoke in two rooms which are so essential to the comfort of my family, and which, after many trials, have led to the adoption of the following plan, being partly new, and partly

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The apparatus is strong and simple, all of cast iron, and may be used with any grate. It consists of a long upright back, as high as the mantlepiece, with open perpendicular ribs behind the fire-place, the height of the grate. This back divides the vent into two branches, which are opened or shut at pleasure, by means of a damper in the throat of the chimney. That damper is inclosed in an iron case, or box, of an oblong square form, and is half the breadth of the box, having ends the whole height of it, so as to continue the contraction to the top of the box, whichever branch of the vent may be open. The box is supported by arms from the back of the grate, and the damper is worked by a handle, which has a knee to it, to let it come out under the breast of the chimney, with a brass knob on the end of it, and has a neat appearance. The sides of the chimney are finished in the usual manner, with cast-iron, brass, or steel plates; and the corners are neatly built up, so as to leave no access to the air, unless through either branch of the vent. The back of the chimney, opposite to the fire, is lined with fire-brick, or fire-tile, to resist and throw back the heat; and there is a sliding shutter at the bottom of the branch of the vent behind the grate, which may be drawn out when the grate is cleaned, to allow any ashes to fall down, and be taken away, which may have got into it through the open ribs.

In lighting the fire, the damper is drawn out to open the branch of the vent behind the grate; and only a small quantity of fuel should at first be used, such as will easily inflame, leaving as much of the ribs open as may be convenient, at the back of the grate. When the vent has become warmed, and the cold air has been expelled, more fuel may be free

ly

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