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quisite national literature. We could think of on to such men as Brown and Mill and Mackintosh old Nicol Burn, the violer, till our eyes filled with and Hamilton (in favor of the last of whom even tears.
Germany has resigned her philosophic interregBut minstrel Burn cannot assuage
pum), the specially literary energy which had His woes while timo endureth,
been awakened in the country descended along To see the changes of this age
another line in the persons of Scott, and Jeffrey, Which fleeting time procureth.
and Chalmers, and Campbell, and Wilson, and Full many a place stands in bard case Where joy was wont beforrow,
Carlyle. Considering the amount of influence exWith Humes that dwelt on Leader side,
erted by such men upon the whole spirit and And Scotts that dwelt on Yarrow.
substance of British literature-considering how
disproportionate a share of the whole literary prodThere was literature in the times when such old uce of Great Britian in the nineteenth century strains were sung. But the true avatar of the has come either from them or from other ScotchScottish mind in modern literature, came later men—and considering what a stamp of peculiarity than the manifestation of the same mind in phi-marks all that portion of this produce which is of losophy. Were we to fix a precise date for it, we Scottish origin, it does not seein tvo much to say, should name the period of Burns' first visit to that the rise and growth of Scottish Literature is Edinburgh, and familiar meetings with the nien as notable a historical phenomenon as the rise and of literary talent and distinction then assembled growth of the Scottish Philosophy. And considthere. Edinburgh was, indeed, even then, a literary ering, moreover, how lately Scotland has entered capital, boasting of its Monboddos, and Stewarts, on this literary field, how little time she has had and Robertsons, and Blairs, and Mackenzies, and to display her powers, how recently she was in Gregories—men who had already begun the race of this respect savage, and how much of her savage literary rivalry with their contemporaries south of vitality yet remains to be articulated in civilized the Tweed. But, so far as the literary excellence books, may we not hope that her literary avatar is of these men did not depend on their participation but beginning, and has a goodly course yet to run? in that tendency to abstract thinking, which had From the Solway to Caithness we hear a loud already produced its special fruit in the Scottish Amen! Philosophy, it consisted in little more than a reflection or imitation of what was already com
From the Edinburgh New Phil. Journal mon and acknowledged in the prior or contemporary literature of South Britain. To write essays on the Physical Geography, Geology, and Comsuch as those of the Spectator ; to be master of a mercial Resources of Lake Superior.* By J. J.. style which Englishmen should pronounce pure, and Bigsby, M. D., late British Secretary to the Canato produce compositions in that style worthy of be- dian Boundary Commission, &c. Communicated ing ranked with the compositions of English authors by the Author.t --guch was the aim and aspiration of Edinburgh literati, between whom and their London cousins
1. Physical Geography. there was all the difference that there is between LAKE Superior is included between W. longithe latitude of Edinburgh and the latitude of Lon- tude 84° 18' and 92° 19'—and N. latitude 46° 29 don, between the daily use of the broad Scotch-49° 1'. It is to the east of, and near to, the dialect, and the daily use of the classic English. swell of high land which, stretching from the For Scotland this mere imitation of English models Rocky Mountains to Lake Superior, in wide unduwus but a poor and unsatisfactory vein of literary lating plains, divides the waters of the Mexican enterprise. What was necessary was the appear-Gulf from those of Hudson's Bay ;-and, then, ance of some man of genius who should flash bifurcating, one fork proceeds on the north side of through all that, and who, by the application to Lake Superior eastward towards Labrador, in literature, or the art of universal expression, of groups of broken hills, while the other fork passes that same Scottish habit of emphasis which had south-east as a rough and high country into the already produced such striking and original results lowlands of the United States. It therefore occuin philosophy, should teach the Scottish nation its pies an oblong crescent-shaped hollow, with true power in literature, and show a first example general direction rather to the north of east. It of it. Such a man was Burns. He it was who, has literally thousands of lakes on its north, and uniting emotional fervor with intellectual emphasis, hundreds on its immediate south. It is 1650 miles and drawing his inspiration from all those depths round, 420 miles long, and 163 in extreme breadth. of sentiment in the Scottish people which his It is 597 feet above the Atlantic. Its greatest predecessors, the philosophers, had hardly so known depth is 792 feet. Soundings of 300, 400, much as touched, struck for the first time a new 600 feet are common; but extensive shallows and chord, and revealed for the first time what a Scot- Hats prevail in parts. tish writer could do by trusting to the whole The hydrographic basin of Lake Superior is wealth of Scottish resources. And from the time singularly sınall
, particularly on the south shore, of Burns, accordingly, there has been a series of where the tributaries of the River Mississippi and
eminent literary Scotchmen quite different from Lake Michigan often approach within 5 and 10 that series of hard logical Scotchmen who had miles of the lake. It seems to be its own fountaintill then been the most conspicuous representatives head. of their country in the eyes of the reading, public
The water is clear, greenish, extremely pure, of Great Britain a series of Scotchmen displaying to the world the power of emphatic sentiment * The statements in this communication are partly deand emphatic expression as strikingly as their rived from the able reports and charts of Messrs. Bayfield, predecessors had displayed the power of emphatic Logan, Foster, Owen, and others in the service
of the reasoning. While the old philosophic energy of governments of Great Britain and the United States
Bigsby's own researches on the northern shores of the Scotland still remained unexhausted, the honors Lake, for 440 miles, having supplied the remainder. of Reid and Hume and Smith and Stewart passing! + Read in the Royal Institution.
pleasant to the taste, and soft from the nearly 1" Dead Sea ;" every living thing is gone, save the total absence of limestone from these regions. An shivering inhabitants of some few white settleimperial pint only contains goboth part of a grain ments. The Indian and the wild animals have of mineral matters-carbonates of lime and mag-retreated to the warm woods far away; and the nesia, sulphate of lime, peroxide of iron, and the sun looks down, from a bright blue sky, on the oxide of manganese.
leaden waters, now narrowed by huge fields of ice The average annual temperature of the water is -a small dark speck on an almost illimitable ex40° F.; being about the same as that of the ocean panse of snow. at certain great depths. In June the lake is often On the south shore, there are in the extreme covered with ice ; and in the middle of July the east, high terraces and treeless plains of blown sand surface-water freezes in the morning-with patches for many miles inland and along shore, succeeded of snow in the clefts of the rocks. At this period by the high sandstone precipices, called the of the year, or a few days later, the smaller lakes Pictured Rocks, battered into fanciful shapes by on the north are steadily at 72o and 74° F.
the violence of the waves. Then comes a low Lake Superior is not undergoing secular drain. rocky coast for 300 miles or more, backed by dense age. It is lowest in April, and highest by a few forests, often mountainous, as at the Huron, Bofeet in September. The great annual variations hemian, and Porcupine Mountains. The scene of rain of these countries produce corresponding is dark with the verdure of northern evergreens, changes of level. There are no tides, and no cycle and is here and there diversified with small clearof years for lake-levels.
ings, and the smoke of distant mines ascending Burometric changes produce curious local oscilla- among the uplands. The bays are often deep, full tions of level. Thus the furious rapids, called the of little iron-stained streams ; and the promontories Falls of St. Mary, on the river of discharge so named, stretch for miles into the lake. are sometimes left dry. Messrs. Foster and Whit- The eastern and northern shores are different ney have seen the oscillation come from the centre more naked, steeper, ever abounding in domeof the lake in a wave 20 feet high-curling over shaped hills, or in ridges, rising by steps, scantily like an immense surge, crested with foam, and covered with trees either stunted or scorched with breaking on the shore, diminishing as it ap- fire. (Large sketches were exhibited representing proached it. On this occasion (Aug. 1845) it was the lofty basaltic country about Fort William, and the harbinger of a violent storm.*
the softer hill-scenery of Black Bay.) The amount of water leaving the lake is small; With the exception of the Fur trading stations, for its outlet is often shallow, and the current there are no white settlements on the north shore ; weak.
and this from its general barrenness. At the Peak The Climate is more arctic than temperato, River, soil was imported in bags with which to raise although the lake is but little to the north of a few potatoes. Milan. It is much colder than Sikla, in Russian The Fauna and Flora of Lake Superior are semiAmerica, 10° further north ; because the latter is arctic, or subalpine. Professor Agassiz has treated screened from polar winds. Winter begins in the of both in his late valuable publication on this middle of October by a succession of "gales and lake. He found twenty-three new species of fish, snow-storms; and from November till May the and states that Lake Superior constitutes a special ground is covered with close-packed, granular ichthyological district. The reason of this evidentsnow; but the earth is not frozen deep, so that, in ly lies in the coldness and extreme purity of the spring, before all the snow is gone, the forest is in water, its slow departure towards the ocean, and leaf. The annual range of the thermometer is the absence of weedy bays and of lime rocks. 125° F.; the mean 42° 14' F.; the lower extreme- It would seem that some portion of its animal 31°, the higher 94°; all these observations having life are waifs and strays from grand geological been made by good observers, with excellent in- periods long passed away—as we see in its herstruments. August is the hottest month. rings, minnows, and the new genus Percopsis. Con
On a mean of twelve years, the winds blow about nected with this subject, Prof. Agassiz conjectures equally from all quarters ; from the NW. the most that much of North America was dry land when frequently-from the south the least frequently.
the rest of the world was under water ; and that The scenery of Lake Superior is striking ;—its thus its physical condition was less altered than elsefeatures are large and open (of which an example where. Dr. Bigsby was inclined to believe this ; was shown in a Sketch of the East Coast.) The for had Canada been as long under water as other eye ranges over high lands and shoreless waters. large tracts, we should probably have had, in some The scanty and dwarfed woods of the north coast, part of its vast extent, a member or two, at least, the rocks, isles, and rivers full of cascades, have an of the mesozoic rocks ; but there is no such thing inipress of their own-not warm, soft and um- -not a single relic of lias, oolite, or chalk, in the brageous, like those of Lake Erie ; but rugged, extraordinary heaps of debris which overspread bare, and chill-arctic. The scene ig oceanic—the these countries. waves are large and high. Some of the plants, the Lathyrus maritimus and the Polygonum maritimum,
II. Geology. for instance, on the beaches, and many of the in- The rocks of Lake Superior have been arranged sects disporting about, are those of the distant under three principal heads, as follows : Atlantic.
1. The Metamorphic.--Greenstone, chloritic, talIn winter, Lake Superior might be called the cose, clay, and greenstone slates, gneiss, The place and extent of these rocks having been of the sandstone ; and is almost invariably placed pointed out on a map, Dr. Bigsby stated that the between it and the trap. geological system of Lake Superior is a consistent The conglomerates of Keweenaw and Isle Royale and closely connected whole, forming a beautiful consist of rounded boulders of trap, with a few and easily read example of geological action in jaspers, cemented by red iron sand; but those of moulding the surface of our globe.
quartzite, jasper, rock and saccharoid lime* A violent gale of wind, concurring with a local rise
stone. of level, will sometimes throw large stones or logs of
2. The Aqueous.-Calciferous sandstone, Camwood 150 to 200 yards inland, and 30 to 40 feet above the nsual water margin-as in three instances seen by Prof.
brian sandstone, and conglomerates. Agassiz (L. Superior, pp. 95 and 106), and by Dr. Bigsby
3. The Igneous.-Granite, Syenite, Trap in va(Jour. Roy. Inst. xviii. 15).
Memince and Nipigon contain also granites, quartThe lake may best be presented at once to the zites, and sandstones ; thus indicating a difference mind as a trough or basin of Cambrian (or Silurian) of age. sandstone, surrounded and framed, as it were, by 3. Igneous Rocks.—Granite everywhere forms two orders of rocks, in the form of irregular and the nucleus of an anticlinal axis, in two parallel imperfect zones ; the inner consisting of trap, with lines running E. and W. on the south-east side of its conglomerates ; and the outer, of metamorphic, the lake, flanked by metamorphic and sedimentary flanking igneous rocks.
rocks. Both it and syenite are plentiful. 1. The Metamorphic rocks, with the exception Trap Rocks.—The ancient lavas of the lake are of quartzite and jasper, are the oldest in the lake, in very large quantities, and are well displayed. and support great sheets of the above-mentioned They are the great depositories of copper. For sandstone unconformably; all these rocks being convenience sake, they may be divided into three upheaved and altered by the intrusion of igneous principal forms. rocks in instances innumerable. This group of 1st. The highly crystalline mountain masses rocks is entirely destitute of the traces of animal -sometimes anticlinal and syenitic. life.
2d. The bedded trap, at various angles of inThe country they occupy on the south shore, clination. with a general NNW. dip, may be best described 3d. Dikes intersecting igneous and metamoras a rough table land of the various slates, out of phic rocks. which short hills of granite, gneiss, trap, &c., They are all portions of one long series of volemerge in great numbers, with an almost constant canic operations. east and west direction.
Trap creates the great headland of Keweenaw, On the east and north shores the metamorphic with its lines of stair-like cliffs and bills. (It was rocks have a W. and WSW. strike, when visible. shown in a large diagrain, and described as typical The slates of the north side of Michipicoton Bay of the trap of the whole lake.) The trap of Keweerun WNW., NW., and N.
naw is met with in three contiguous and parallel The jasper and quartzite are merely altered sand- belts, going WSW., and separated by bands of stone, and therefore younger than the other rocks conglomerate, sometimes very thin, often numerous, of this group.
and prolonged sometimes for 40 or 50 miles. These 2. The Aqueous Rocks.—The youngest of these three belts have been named the outer, northern, is calciferous sandstone. It exists as a broad band and southern ; the last being highly crystalline, on the south-east shore, resting on the sandstone or syenitic, and abounding in chlorite. It is an soon to be noticed. It is highly magnesian and anticlinal to the rocks on both sides. The other two siliceous in parts. A patch of it in Grand Island belts are bedded traps, and with their interleaved contains shells. (Logan.)
conglomerates dip northerly. They all coalesce at The Cambrian Sandstone seems to be the floor or Portage Lake, and, after proceeding to Montreal basement of nearly all the lake, for the following River, 130 miles in the whole, soon after disappear
under horizontal sandstone westwards. 1. Wherever it occurs, whether in immense The north belt is the most metalliferous; and
sheets on the east and south shore, or in contains the celebrated Cliff and other rich mines. smaller areas on the north coast, it in- In the Keweenaw district it is the cross vein which
variably dips towards the centre of the lake. yields the native copper-either in sheets and 2. It can be recognized, paving the lake for blocks or mixed in with the usual crystallizations,
some miles from the main in many places. such as datholite, prehnite, stilbite, quartz, &c. 3. The soundings of Captain Bayfield exhibit, On the Ontonagon River the metalliferous veins
for large spaces, the uniformity of level to run with the strike. The copper is pure, and has be expected from the presence of horizontal interspersed through its substance scales of pure strata.
silver; but without chemical union. 4. Because it constitutes Caribou Island, 40 The copper is confined to the trap, as a universal miles from the nearest main land.
rule. This sandstone is very ancient; and is supposed The north shore of Lake Superior is eminently by Mr. Logan to be Cambrian on the north shore, trappose ; and especially about Fort William, and lower Silurian on the south—a supposition, the where a region at least 120 miles long consists of latter clause of which, though extremely probable, basalt, amygdaloid, porphyries, jasper, conglomeris not yet established.
ate, and sandstone in the same mutual relations It has no fossils ; but its ripple marks, impres- as on the south shore. sions of rain-drops, and sun-cracks, are plentiful The trap dikes, traversing granites and other and perfect.
crystalline rocks indifferently, are a singular feature It is more commonly red, and is composed of the on the north shore, and abound chiefly from Writdebris of granitoid rocks, in nearly horizontal strata, ten Rocks to the bottom of Michipicoton Bay. By except near intrusive rocks, when it rises to a high their dark and undeviating course through the gray, angle, hardens, and even passes into true jasper, red, or green rocks of the rugged coast, they strike porphyry, gneiss, or quartzite. There is reason to the eye of the most incurious—if only as ruined think that this sandstone is interleaved with trap. staircases, crossing bays and headlands, and climb (A Landscape was exhibited of the Sandstone ing hills for miles. Their size, number, and direoRocks, soutá shore.)
tion are irregular. They may be solitary, or twenty The conglomerate is of the same age with much I in company—sometimes all parallel and close to
gether. They often run with the general trend of brought characteristic fossils. Another is found in the coast.*
the occurrence of boulders of iron ore, in heaps, on Mr. Logan divides them into three varieties, the north side of certain cliffs, but which are according as they are homogeneous, syenitic or absent on the south side-the original site of the porphyritic.
ore being to the north of the cliffs, and near Lake Professor Agassiz distributes the dikes of the Superior. whole lake into six systems—each with its own A sketch was exhibited of a Wisconsin prairie, mineral character and direction—its own epoch of dotted wit northern blocks dropped from icebergs. upheaval; and each he announces to have been an - From Dr. D. Owen. important agent in giving shape and direction to the district in which it occurs. He truly says that the
III. Commercial Resources. general outline of the lake is the combined effect Agriculture will only be carried on in parts of of many minor geological events taking place at the south shore. Large quantities of white fish different periods. With some truth in it, this and of furs are annually exported. theory does not seem to take into sufficient account The chief staple of Lake Superior is native copthe preëxisting metamorphic and granitic rocks, per. For ages before the appearance of Europeans and it overlooks the variety observed in the direc- in America, this metal was supplied from hence tions of the dikes in the same neighborhood.
to the Indian nations far and near. The tumuli Dr. B. stated that if he might be allowed to of the Mississippi, &c., contain the identical cophazard an opinion, it would be, that this curious per of this lake. Traces of ancient mining in assemblage of dikes—abounding as much in the S. Keweenaw, Ontonagon, and Isle Royale, are abunas on the N. coast-pervading all the crystalline dant, in the form of deep pits (a ladder in one), rocks indiscriminately, had ascended independently rubbish, stone mauls, hammers, wedges, and from the unseen, distant mass of trap beneath. chisels of hardened copper. In a native excavaThey appear in many ways peculiar, and have no tion, near the river Ontonagon, with trees five visible connection with the traps he had been de- hundred years old growing over it, lately lay a scribing.
mass of pure copper, 81 tons in weight, partly Before the emergence of either traps or granites, fused, and resting on skids of black oak. Lake Superior received its great outlines from the Modern explorers have hitherto only found two metamorphic rocks—thrown into their present centres of metallic riches on the south coast—that position by still earlier upward movements; for, on of Keweenaw and of Ontonagon. In the first are the eastern half of both shores of the lake, they the valuable mines of the Cliff, North American, strike E. and W. with little variation; while on North-Western, and other companies. In the the western half, these far extending rock-masses Ontonagon centre are the Minnesota and fifteen strike WSW. and SW.-giving thus to the lake other mines. a general eastward direction, with a gentle curve At the Cliff mine three large steam engines are to the north, as stated before. This done, Cam- employed (1852); with 250 men ;-and at the brian sandstone slowly took possession of the trough North American mine, two engines, with 160 men. of the lake—just as we see a certain shell marl is Most of the other mines, forty in number, are asdoing now. The anticlinal granites, which ap- sisted by steam-power. Three thousand miners peared afterwards, only concurred in the same are in work altogether, and the general population effect; shaping and elevating the adjacent lands. is fast increasing. Native copper is the principal
In after-geological times important modifica- object. Silver is always present, and occasionally tions arose in the form of the lake. Promontories in masses of considerable size. According to were pushed out, and islands raised up by succes- authentic accounts, dated February, 1852, many sive outbursts and overflows of trap from separate new mines have been opened lately; and all are fissures of great length—those, for example, of worked more systematically than heretofore-genKeweenaw, Thunder Mountain, and Isle Royale- erally by contract. all intercalated with conglomerates, formed in There are now in the Cliff mine masses of pure agitated seas between eruptions ; -—at different and copper within view estimated to weigh 700 tons most probably distant times, judging from the in the whole ; and on the lands of the Minnesota fact that some of the conglomerates are altogether Company, one block weighing 250 tons. The cop trappose, while others abound in granite and other per shipped in 1851 was about 1600 tons, valued boulders.
at £130,000. This copper is stated to be of great We thus obtain the general order of all these excellence in the manufacture of wire, ordnance, events, and little more ; but the knowledge is and ship-sheathing. worth having. From the position of the uplifted The large beds of specular and magnetic iron mural cliffs, we see that the upheaving impulse ore, on the south-east side of the lake, are as yet came from the south-east.
only worked on a small scale. Drift.-The groovings and striæ are almost al- Åt this moment the business of mining has ways northerly here. New proofs are daily accumu- ceased on the Canadian side of the lake. There is lating to show more decisively the northerly origin little doubt, however, but that profitable deposits of the foreign drift of Lake Superior. One of these will, sooner or later, be discovered here. is the fact that the limestone boulders on the Dorth shore are upper Silurian,t and derived from the large calcareous basins some hundreds of miles SELF-INDULGENCE takes many forms, and we should north of Lake Superior; from whence Dr. B. had bear in mind that there may be a sullen sensuality suis From the Quarterly Journal of the Chemical Society. engine-room, from which they would be protected Chemical Report to the Lords of the Committee of by the double partition. I have obtained instances
well as a gay one. • Vide Quart. Journal of Roy. Inst., vol. xviii., p. 244. RUNNING after happiness is only chasing the hoBigsby on Lake Superior.
rizon. † Containing Pentamerus, Spirifer, Leptæna (alternata) atrypa, various corals, minute trilobites, orthocers, and KINDNESS pains more than cruelty when it is given come cytherinæ.
instead of love.
Privy Council for Trade, on the Cause of Fire in where coals took fire in a factory, on two different the Ship Amazon. By Professor GRAHAM. occasions, by being heaped for a length of time
against a heated wall, of which the temperature My Lords,-In reply to the questions arising could be supported by the hand ; also of coals out of the disastrous loss of the Amazon by fire, igniting after some days upon stone flags covering which are proposed to me for a chemical opinion, I a Aue, of which the temperature was not known to beg to subinit to your lordships the following state- rise above 150°, and of coals showing indications ments and conclusions.
of taking fire by being thrown in bulk over a The practice of mixing together the various steam-pipe. These were Lancashire coals, which stores of the engineer, consisting of oils, tallow, are highly sulphureous; but the same accident oc soft-soap, turpentine, cotton-waste, and tow, and curred with Wallsend coals, at the Chartered East placing them in heated store-rooms contiguous to Company's Works in London, where the coals the boilers, must be looked upon as dangerous in were twice ignited through a two-feet brick wall, no ordinary degree, for several reasons. Although of which the temperature was believed by Mr. oil in bulk is not easily ignited, particularly when Croll not to exceed 120° or 140°. preserved in iron tanks, still, when spilt upon The surface of deal, in the partition opposed to wood or imbibed by tow and cotton-waste, which the boiler, would probably be better protected expose much surface to air, the oil often oxidates from fire by impregnating the wood with a saline and heats spontaneously, and is allowed to be one solution, which diminished combustibility, such as of the most frequent causes of accidental fires. The the zinc solution of Sir W. Burnett, rather than vegetable and drying oils used by painters are by coating the wood on the side next the boiler most liable to spontaneous ignition, but no kind of with sheet-iron. Indeed, this use of iron appears animal or vegetable oil or grease appears to be to introduce a new danger. The iron being a exempted from it; and instances could be given of good conductor of heat, the wood below is heated olive-oil igniting upon saw-dust; of greasy rags nearly as much as if uncovered, and wood in confrom butter, heaped together, taking fire within a tact with iron appears to be brought by repeated period of twenty-four hours ; of the spontaneous heating to an extraordinary degree of combusticombustion of tape-measures, which are covered bility, and to become peculiarly liable to spontanewith an oil-varnish, when heaped together, and ous ignition. oven of an oil-skin umbrella put aside in a damp Mr. Braidwood, who has been led to that constate. The ignition of such materials has been clusion, gave an instance of wood covered by sheet often observed to be greatly favored by a slight iron igniting spontaneously in a wadding manufacwarmth, such as the heat of the sun. I am also tory. The numerous occasions, also, on which informed by Mr. Braidwood, that the great pro- wood and paper have been ignited by Perkins' portion of fires at railway stations have originated heated water-pipes, equally exemplifying the danin the lamp-store, and that in coach-works also, gerous consequences which may arise from moderwhen the fire can be traced, it is most frequently ately heated iron, in long contact with combustible to the painter's department, the fire having arisen matter. spontaneously from the ignition of oily matters. The most obvious precautions for guarding Lamp-black and ground charcoal are still more in- against the spontaneous ignition of coal stowed in flammable, when the smallest quantity of oil ob- ships' bunkers, appear to be the taking the coal tains access to them, and should not be admitted on board in as dry a condition as possible, and the at all among ship's stores.
turning it over, if there be room for doing so, as The stowing metallic cans or stoneware jars of soon as the first symptom of heating is perceived. either oil or turpentine in a warm place, is also An obnoxious vapor is described as always precedattended with a danger which is less obvious, ing the breaking out of the fire, and affords warnnamely, the starting of the corks of the vessels, or ing of the danger. The ignition of Newcastle coals the actual bursting of thetn by the great expansion in store, is not an unfrequent occurrence at the of the liquid oil, which is caused by heat. These London gas-works. It appears always to begin at liquids expand in volume so much as one upon a single spot, and is met by cutting down upon and thirty, by a rise of not more than 60° of tempera- removing at once the heated coals. Long iron ture, or by such a change as from the ordinary low rods are placed upright in the coal heap, which temperature of 40° to a blood heat ; the latter can be pulled out, and indicate by their warmth temperature may easily be exceeded in an engine- the exact situation of the fire. Steam can be of
It is remarkable that the burning a few little avail for extinguishing the fire among the years ago of a large steamer on the American coals in bulk; and water, although it may exlakes, which even surpassed in its fatality the loss tinguish the fire for the time, is too apt to induce of the Amazon, was occasioned by the bursting, in a recurrence of the evil. the manner described, of a jar of turpentine placed For extinguishing a fire occurring in berths or upon deck too close to the funnel, by a party of cabins in the immediate vicinity of the boiler and journeymen painters, who were passengers. This engine-room, steam might be more advantageously steamer was also on her first voyage, and, being applied, means of turning on the steam being pronewly varnished, the fames spread over her bul- vided upon the upper deck, or other distant placo warks and extended the whole length of the vessel of safety. Steam, however, can only be said to be in a few minutes.
efficient in extinguishing fame, or a blaze from The bulkheads of coal-holds appear to admit of light objects, and is not to be relied upon beyond obtaining considerable security from fire by being an early stage of a fire. Upon a mass of red-hot constructed double where close to the boiler, with cinders the extinguishing effect of steam is insena sheet of air between the two partitions. The sible. tendency of coals to spontaneous ignition is in- An essential condition of applying steam with creased by a moderate heat, such as that of the success to the extinction of a fire in the engine