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ART. XXI.-Description of an Apparatus for Restoring the Action of the Lungs. By Mr JOHN MURRAY, Lecturer on Chemistry. Communicated by the Author.

EVERY

person who knows the fine movements of the lungs, and their beautiful isochronism, will wonder that the bellows can in any case be efficient in restoring their action. The pressure on the chest, in the ex- pulsion of the air injected by this machine, is as rude and unequal as the action of the bellows itself is variable, directed, as it often is, by the error and caprice of an unskilful hand; and even the forces will at all times be balanced with difficulty by the best directed efforts of the most dexterous operators.

We have only to look at those numerous unsuccessful cases, which appeared so promising, to draw the painful conclusion, that the instrument commonly used, is quite unfit for the purpose, and that there still is a valuable desideratum to be accomplished.

Impressed with the magnitude of the subject, I have drawn up the following description of an apparatus, which seems calculated to supply the defect; and I am happy to say, that it has met with the decided approbation of such medical gentlemen and mechanists as I have explained it to.

Description of Fig. 8. Plate III.

A, is a cylinder, in which the piston-rod moves, having a solid piston, and passing at top through a close collar of leather. B, the piston-rod. C, represents a cylinder of tin, with a partition concentric with it, which partition receives water (at a) heated to 98° Fahr.. (the animal temperature), et infra, and of course raises the air within the canister to the same temperature. b, is a canal and stop-cock connecting the air cylinder with the pump, and becoming the medium of supply. When asphyxia is occasioned by carbonic acid gas, a few drops of ammonia in the air-cylinder will be eminently serviceable, in the first instance; for unless this air be abstracted or neutralized, we shall endeavour in vain to excite the suspended ener

gy of the lungs; and as a drop or two of ether might be occasionally useful as a stimulant, (since it appears that a mixture of etherial vapour and atmospheric air produces all the effects of nitrous oxide), it may be conveniently applied through this appendage.

D, is a bladder and stop-cock for the occasional administration of oxygen or nitrous oxide.

E, is a flexible hose, similar to that in the common apparatus,

with a stop-cock to cut off or restore the communication at its entering the larynx, and b is a perforated tube, with a safeshield which closes the vent, and that tube is maintained in its place by the fixation of a ribbon round the head of the victim of suspended animation.

c, is a valve resembling the key of a flute, and operating similarly; for, by pressing the farther end of the lever, the aperture is uncovered, and, by a spring, it recovers its wonted place. It serves to empty the cylinder occasionally, and prior to the re-supply of new air from the attached air-cylinder.

d, is a curved canal, uniting the space below the valve with that above it, when the piston ascends to the dotted line g. f, is a joint, by which the tube is made to slide into itself like the tubes of a telescope, and thus regulate the size of the volume of air for lungs of any required capacity.

e, is the button-valve, which is raised by the air escaping from the lungs, and filling the space prepared by the ascending piston; and the same elevation of the valve uncovers the orifice of the canal h, and the air rushes through it so scon as the piston-rod mounts to g, and fills up the space which obtains between the orifices at the dotted line g and the valve e. From this description, the mode of using the apparatus must be evident.

ART. XXII.-Notice of the Progress of the Arctic Land Expedition under the command of Lieutenant FRANKLIN. In a Letter to Professor JAMESON *.

[DEAR SIR,

London, November 26. 1820.

KNOWING the lively interest you take in the progress of geographical discovery, and having observed in the 1st volume of the Edinburgh Philosophical Journal a short account of the plan of the Arctic Land Expedition, I use the liberty of transmitting to you an extract from a journal dated Cumberland House, June 1. 1820, lately received from Hudson's Bay, and which brings up the progress of Lieutenant Franklin's expedition to the 1st of June last. I remain, &c.]

AFTER leaving York Fort, the expedition ascended Hayes,

Steel, and Hill Rivers, which, with a series of small lakes, and their connecting streams, form one continued line of water communication to the Painted Stone. Over the low rock which has obtained this name, the boats were launched into a rivulet named the Echemamis, which we descended till its junction with a branch of Nelson River. Proceeding up this branch, and passing through Play-green and Winnepeg lakes, they entered the Saskatchewan, and navigated it as far as Cumberland House, the wintering station of the expedition.

York Fort is situated on a point of alluvial land which sepa rates the mouths of Hayes and Nelson Rivers. Throughout the whole length of Hayes River, the country has an uniform low, flat, swampy appearance. The soil consists of decayed moss, immediately under which there is a thick bed of tenacious bluish clay, containing imbedded rolled stones. The stream continually encroaching upon some points, and depositing its spoils in others, renders its banks alternately steep and shelving; but in general, the bed of the river is scooped out in this clay to the depth of thirty or forty feet. The plain above is covered with stunted larches, poplars, alders, and willows. Hayes River is formed by the junction of the Shammattwa and Steel Rivers; and the latter branch is in like manner produced by the union

• Read before the Wernerian Society, December 2. 1820.

of Fox and Hill Rivers. During the ascent of Steel River, the banks gradually increase in height; and in the lower part of Hill River, they exceed 300 feet. These high clayey banks are broken into conical hills by the deep ravines which open into the river. The travellers had no opportunity of judging of the nature of the interior; but wherever the current had worn the bank, the section exhibited only the clay above men

away

tioned.

About 90 miles from the sea-shore, a ridge of primitive rocks presented itself, crossing the bed of the river, and producing a fall termed the Rocky Passage. Above this spot, the banks of the Hill River gradually decrease in height, the channel continuing uniformly rocky, and at length the superincumbent clay entirely disappears, leaving the rocks on the borders of the stream either quite naked, or partially covered with soil, and clothed with trees. Eight or nine miles above the rock-portage, there is a small range of conical hills, the most remarkable of which is termed the Hill, and gives the name to the river. It is from 500 to 600 feet high. Above this hill, the shores were low and rocky, but the woods concealed the interior from our view. The rocks seem to be primitive; and the flatness of the country was ascribed to the abundance of the water, which, filling the valley's, generally so deep in this formation, leaves the summits of the ridges alone uncovered. Thirty-five lakes are visible from the top of the Hill. No material variety in the appearance of the land was observed before they arrived at the Painted Stone; and even after crossing into Nelson River, the same species of rock was seen exposed.

At the entrance of Lake Winnipeg, an alluvial stratum again covers the rocks to an unknown depth. It differs a little from the clay through which Hayes River runs, in being of a whiter colour, and probably in containing a considerable portion of calcareous matter. Calcareous rocks make their appearance in great abundance on the western side of Lake Winnipeg, the whole country for at least 300 miles along the course of the Suskatchewan appearing to be composed solely of them. There is a fine section of them at the Grand Rapid, near the mouth of the river. At this place, the stream forces its way through a chasm about 60 feet deep, the rocks on each side being disposed in thin

strata, dipping to the northward at an angle of 10°. The rocks yield readily to the conjoined actions of the water and the atmosphere, and fall into the river in large cubical fragments, which soon separate in the direction of the strata, into layers. The prevailing colour of the stone is cream-yellow; and it appears to contain a considerable portion of clay, as it adheres to the tongue when broken. It burns into a very white lime, but it requires to be a long time exposed to the action of the fire. We could not find any other rock associated with this limestone, nor could we discover any organic remains in the rocks in their native situation; but some small fragments lying loose amongst the soil, contained shells. The banks of the Saskatchewan, for the distance above mentioned, are low and swampy, but in many places the limestone shews itself above the surface. It exhibits a surprising uniformity of appearance.

During the winter, an excursion was made to Beaver Lake, about 40 miles to the northward, and the rocks were still found to be calcareous, but of a more crystalline texture, and varying in the colour, and in the direction of the strata. On the borders of the lake, there are small hills and mural precipices of both red and yellow limestone. There are many deep rents in the rocks here, and the lake in some places is 15 fathoms deep.

To the southward of Cumberland House, there is a roundbacked hill, about 40 miles long, which the expedition had not an opportunity of visiting. It is visible about 30 miles off, and exhibits an even outline; but we were told, that a near approach shews it to be rugged. There are several springs at its base, which afford a considerable quantity of salt.

The river was traced about 240 miles above Cumberland House to Carlton House. There the country is entirely alluvial, consisting of extensive sandy plains, and nearly destitute of wood. These plains, about 200 feet above the present bed of the river, appear to have been covered at no very distant date. From the summit of the plain to the river, a regular gradation of three or more banks may be traced, shewing the height at which the river has flowed at different periods. Amongst these banks, the river shifts its bed continually, encroaching, on the one side, on the deep bank of the plain, and forming low level points on the opposite shore. The older plains are dry and sandy, and pro

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