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-- owes-o o os-y or overs; and from the nature .* * ********* * ***roction of canals has been a vo-------> *** ****

or ... ....... s.r.o...tva of Mineral Products.

no os o ox avoice of minerals are in veins or o, a vs.- or regular beds, and in connection with low-to waters. The consideration of the disobuuou, or unwals will be treated of under these * -

u \ious on o

onvush it is disticult, in the present state of our knowlov, no woulin the laws regulating the deposit of mouluevu- unauer, yet we are able, from general obovation of the geological structure of the earth; to say onal, he orch unay be made for minerals with some not auco, and that there exploration will be futile, tionala of thousands of pounds have been expended in un-nuuuun up of mineral districts; a large proporu-nut the sum utterly without profit.

o oritain possesses a rich supply of minerals; we have old, silver, copper, lead, tin, zinc, antimony, nickel, o biomuth, uranium, chromium, and other of the out mulas, besides vast stores of iron; our coal beds nauguous, and earthy minerals are in great variety unavalue Batistics show that in Great Britain 350,000 to o actually engaged in mining operations, exMusive of quarries of all kinds, and that the produce is usin, uinimum annual value of £40,000,000.

in-lades from which we derive our chief supply of

- are almost wholly confined to palaeozoic rocks. W in ourrence may be sketched as follows:

s a silurian formation in North Wales, in the Isle of

an in Cumberland, in the lead hills of the south of o - lona, in parts of the Highlands, and in parts o oland, contains metalliferous veins which yield o of copper, lead, silver, antimony, arsenic, and

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wouliar exceptions hereafter to be mentioned, ofed or the associated igneous rocks, not Permian. It is thus that one generalisaoquiry is arrived at, viz., that of the period o' the lodes carrying our richer metals Geology, like the more exact sciences, is of advancing philosophical inductions to very route. Sir Roderick Murchison was en1844, from the study of the gold-bearing tracts ict the discovery of gold in Australia. * Sir R. Murchison, “in the year ormed from the auriferous Ural Moun

o: the world, all the metalliferous lodes, In !"

- collected by Count Strzelecki, along the easter-chain of Australia. Seeing the great similarity if its rocks of those two distant countries, I could hare little di in drawing a parallel between them; in doing which, I was naturally struck by the circumstance, that no gold ‘had yet been found' in the Australian ridge, which I termed in anticipation the “Cordillera.’ Impressed with the conviction that gold would, sooner or later. be found in the great British colony, I learned in 1845 that a specimen of the ore had been discovered. ... I thereupon encouraged the unem. ployed miners of C to emigrate and dig for gold, as they dug for tin in the gravel of their own district. These notices Tere, as far as I know, the first published documents relating to Australian gold" (“Siluria.”) Influence of Igneous Rocks in the Development of Minerals in Weins. Mineral veins occur in igneous rocks as well as in aqueous rocks; but the intrusion of an igneous mass among stratified deposits appears to have rendered their lodes richer than when conditions otherwise similar obtain. Gold is usually found in a quartz matrix, traversing palaeozoic shales, chiefly those of the lower Silurian epoch; and the auriferous lodes are frequentlyrichest in the vicinity of eruptive rocks. But the precious metal is found also in secondary rocks, such as those of California, Peru, etc., yet under circumstances exceptional to the usual mode of association of gold. It appears that where certain igneous eruptions, diorite especially, have penetrated the secondary strata, the latter have been rendered auriferous for a limited distance only beyond the junction of the two rocks; and it is concluded that all secondary and tertiary deposits (except the auriferous detritus of the latter), not so specially affected, never

contain gold. Devon are richest about the junction of the killas (local name for the slaty rocks of the Devonian formation in this district), and the bosses of granite, and where they worthy of remark that these metalliferous veins have a course or strike nearly east and west, and that these henomena are not confined to this area, but are exhibited Other examples might be adduced, but these suffice to show that intrusive rocks influence the in liferous richness of veins. These include coal and iron ore of primary importance and salt, gypsum, cement-stones, coprolites, iron-pyrites bituminous shales, etc., of secondary value. for upwards of a hundred years at Brora, in Sutherland. shire, in rocks of the oolitic epoch, and is worked a Bovey Tracey, Devonshire, in Miocene beds. An anthro good workable coals of the age of the trias in Virgini and Hindostan, and of that of the lias in Hungary; an less valuable coals, chiefly brown coals, occur in tertiary far the richest and largest supplies are drawn fro carboniferous system in Great Britain, Belgium, United States, Nova Scotia, Australia, etc. strata, but it does occur in newer strata. In the mid land and south-western counties of England, and in Sout by the millstone grit, locally called the "farewell rook because, in the language of the miner, when that rock reached, one bids farewell to the coal. But in the nort

iyantage of examining the numerous

The lodes carrying copper and tin in Cornwall and are intersected by granitic dykes, termed elvans. It is in Saxony and elsewhere. .. 2. Bedded Mineral Deposits. (a.) Coal occursin many formations; it has been mine cite occurs in the Devonian rocks in Spain; there an strata in Austria and other parts of Germany. But by In Great Britain no coal is found below carboniferous Wales, it is confined to the true coal measures undero of England and in Scotland workable coal seams ox" in the inferior formations of the carboniferous system, as well as in the coal measures. The right understanding of the law of superposition of rocks in relation to our coal-bearing strata, is of value not only to the man of science, but to every speculator in mines, and to every landed proprietor who cares to understand the mineral value .P his *:::::::::: Not long ago considerable funds were spent at Tullygirvan, Co. Down, in a useless search for coal. The adventurer had set to work in black Silurian shales, their mineral aspect resembling that of certain coaly strata, with which he was, perhaps, familiar; but had he possessed even a slight acquaintance with organic remains, he would have abandoned his experiment at the commencement, for the shales were charged with graptolites. Now the scientific miner knows that rocks containing graptolites, trilobites, etc., existed untold ages before the epoch of the coal strata; so that when he meets with those remains, he concludes that money spent in search of coal beneath them will be turned into irredeemable dust, for they occupy, in the irreversible order of deposits, a position thousands of feet beneath the coal measures. Lord Londonderry bored in the old red sandstone, at Mount Stewart, Co. Down, in search of coal: here, though no fossils occurred, yet the position of the sandstone strata above the previously mentioned Silurian shales, and overlaid as they are by mountain limestone, proved the impossibility of coal being found. In the joi of Carrickfergus are two silent witnesses of the folly of sinking for coal where the geological structure of the country precludes the possibility of is presence, or of its occurrence at reasonable depths. Trial shafts had been sunk in new red sandstone, which was pierced to a depth of about 1,000 feet, when he adventures were abandoned. Before coal could be eached, the Permian strata would have to be passed hrough; and from the unconformability of the new ed sandstone to the Permian, and of that set of strata 0 underlying formations in this district, it was even oubtful if coal could be reached at all. But coal has been successfully reached by the peneration of newer unconformable strata; thus in the omersetshire coal field, the coal shafts pass through ow red sandstone, the Permian strata being absent. he famous Monkwearmouth pit passes through 330 feet soverlying Permian rocks. In these and other instances that might be adduced le undertakings had been commenced at the suggesons of those who were perfectly satisfied, from an exmination of the surrounding country, of the feasibility of eventure. Yet, on the other hand, attempts have been ade to reach coal from below secondary rocks, when, th but a broad knowledge of the geological structure the country, the trials should have been at the outset andoned. Thus, at Kingsthorpe, near Northampton, shaft was sunk through the lower oolite and lias, at an penditure of nearly £30,000; the adventurers desisted len they reached the new red sandstone. A similar al took place near Lyme Regis, the lias being bored 'coal at an expense of several thousand pounds; the ception was fostered by the accident of passing through wiece of lignite. (b) Iron Ores. Certain ores of iron occur in lodes in primary strata, others, especially the spathic and brown haematite ls, are it.' as bands among shales and limeres of the carboniferous, liassic, oolitic, wealden, and taceous strata; but by far the largest supply is ained from the carboniferous system, the one shaft en communicating with both coal and iron-stone rkings, and the same group of rocks furnishing lime

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Ile,

CORRESPONDENCE IN FRENCH.-W. 17.-FoEM of ADVICE of A TRAVELLER's WIsrt.

Lyons, March 28th, 1864. Messrs. Smith, Cook & Hyde, London. Gentlemen, We beg to inform you that our Mr. Robert Roche will wait upon you to submit to your inspection samples of our latest manufactures in Dresses and Shawls, Waistcoatings, Cravats and Handkerchiefs. Trusting soon to be favoured with a large order, We remain, Gentlemen, Your obedient Servants, LEcouTEUR, GASPARD & Co. Lyon, le 28 Mars 1864. Messieurs Smith, Cook & Hyde, A Londres. Messieurs, Nons avons l'honneur devous annoncer que notre M. Robert Roche se présentera chez vous pour vous soumettre les échantillons de toutes nos nouveautés pour robes, chales, étoffes pour gilets, cravates et foulards. Dans l'espoir de recevoir bientôt une bonne commande, Nous vous présentons, Messieurs, nos salutations empressées, LecouTEur, Gaspard & Co.

18,-LETTER ADVISING DESPATCH of Goods, AND ENCLos ING INvoice London, April 10th, 1866. Phillip Teesdale, Esq., Dublin. Dear Sir, Enclosed please find invoice of Cotton Goods forwarded to-day in a case marked PT No. 5. The amount of this invoice 3450 please place to my credit. Awaiting your further orders, to which my best attention shall always be given, I remain, dear Sir, Yours truly, A. LoNSDALE. Londres, le 10 Avril 1866. Monsieur Phillip Teesdale, A Dublin. Cher Monsieur, Ci-joint j'ai le plaisir de vous remettre facture à des Cotonnades quivous ont été expédiées ce jour dans une caisse marquée PT No 5. Pour le montant de cette facture veuillez me reconnaitre de

2450. Dans l'attente de vos ordres ultérieurs qui auront tous mes soins, Jevous présente, cher Monsieur,

Mes salutations sinceres,
A. LoNSDALE.

19.-LETTER REQUESTING FURTHER ORDERs. Lyons, Dec. 30th, 1865. Messrs. Dufour & Co., Paris. Gentlemen, It is now more than three months since we had any orders from your firm; nevertheless, we are persuaded that the fault does not lie with us, or the manner in which we have executed your last. We are more vexed than you at the rise in velvet, and we know that your sale must in consequence be hampered. If you, however, realise that throughout France and Italy cocoons have fetched from 6 fr. to 6 fr. 90 c. per kilogram—that is to say, 18% more than last year, and that consequently silk costs us more than 18% above last year's prices—you will see the necessity of our raising the price of our velvet in proportion. . You will find in our parcel some samples of what we have in stock, and we subjoin our price list. Our Mr. Marchand will be in Paris next Tuesday, and will have great pleasure in giving you further details. We are, Gentlemen, Truly yours, JAMEs MARCHAND, BRIGAUD & Co. Lyon, le 30 Décembre, 1865. Messieurs Dufour & Cie, a Paris. Messieurs, Il y a plus de trois mois que nous n’avons requ d'ordres de votre maison; mous ne pouvons, pourtant, imaginer que la manière dont mous vous avons traités dans le dernier envoi, ait pu diminuer la confiance que vous nous avez accordée. Nous sommes plus fächés que vous de l'élévation

"prix que vont subir nos velours, et nous sentons bien que cela | Mr. J. Muirhead, et dont vous nous enverrez les reças, permetvous gênera pour la vente. Figurez-vous que les cocons se sont tez-nous de vous exprimer d'avance nos plus vifs remerciements payés partout en France et en Italie de 6 fr. à 6 fr. 90 le kilo- des attentions que vous aurez pour notre recommandé et sa gramme--c'est-à-dire, 18 % plus cher que l'an dernier-les famille. soieries de toute cette campagne vont donc nous coûter 18 % Nous éprouverons toujours le plus grand plaisir à vous rendre de plus que l'an dernier, et il faut que nous augmentions nos le réciproque, ainsi que tout autre service qui dépendra de nous, velours en proportion.

et vous prions de disposer librement de notre ministère. Vous trouverez dans notre envoi quelques échantillons de ce Agréez, Messieurs, l'assurance de la plus haute considéraque nous avons de disponible en magasin, et ci-joint notre note tion de de prix.

Vos obéissants serviteurs, Notre M. Marchand sera à Paris Mardi prochain, et aura le

SPIELMAN & CTE. plaisir de vous entretenir plus longuement de tous ces détails. Messieurs N. N. à Berlin, Vienne, Trieste, Agréez, Messieurs,

Venise, Rome, Naples.
Nos saluts empressés,
JACQUES MARCHAND, BRIGAUD & CHE

21.-LETTER OF INTRODUCTION,

Stuttgard, Jan. 1st, 1840.

Gentlemen (Sir),-We beg to introduce to you the bearer, 20.-CIRCULAR LETTER OF CREDIT, ETC.

Mr. --, whom we recommend to your kindness.

London, March 4th, 1863. We at the same time open in your account a credit of Gextlemen, - This circular letter of recommendation and £1,000, to which amount please furnish Mr. with the credit will be remitted to you by James Muirhead, Esq., of sums he requires upon his receipts, which please send us, when Edinburgh, a gentleman for whom we claim from you a friendly debiting our account for your payments. reception, and we beg you to give him an opportunity of enter Accept beforehand our best thanks for the services you ing into business relations with the large landholders of your will render Mr. --, and believe us to be, Gentlemen (Sir), country. Mr. Muirhead belongs to one of the richest families

Faithfully yours, in Scotland, and himself superintends his extensive and flourish

J. WEBER & Co. ing estates. As he intends looking over the land in the neigh Mr. --, London. bourhood of your metropolis, you will oblige us by paying every Valid for -- months. * attention in your power to his family, who, having accompanied

Slutlgord, le 1 Janvier, 1810. him thus far, will remain a few weeks in your city during his Messieurs (Monsieur),-Nous prenons la liberté d'introduire short absence.

chez vous par ces lignes, et de vous recommander à un accueil As to the funds which Mr. Muirhead will require, we beg to obligeant, M. open a credit with you in his favour for the sum of £5,000 (five Nous l'accréditons chez vous pour la somme de £1,000 (nous thousand pounds sterling), which you will please to pay, indorsing disons mille livres sterling). Veuillez bien payer jusqu'à cette on this letter each of the sums he will have received to the full concurrence l'argent dont M. aura besoin, et nous en débiter amount of his credit. Please add to the amount your com. sous envoi de ses quittances. mission and all other expenses, and draw on us for the whole Nous vous remercions d'avance, de ce que vous voudrez faire sum at the best possible rate of exchange, and at the date en faveur de M. ---, et vous prions d'agréer l'assurance de "customary in your town.

notre parfaite considération, Assuring you that due honour will always meet the drafts for

J. WEBER & CE the payments you will make to James Muirhead, Esq., the M. , à Londres. receipts for which you will be kind enough to send us, we beg to

Valable pour

mois. thank you beforehand for the attentions you will show to this 'gentleman and his family.

We shall always have the greatest pleasure in rendering you CIVIL SERVICE PAPERS.-IV. similar or other services, and begging you to command the same

GROUP III. at any time, We are, Gentlemen,

GROUP III. will be treated in this and one or two subsequent Your obedient servants,

papers. It is the largest of the groups, and comprises the SPIELMAN & Co.

British Museum, the Charity Commissioners, the Civil Service Messrs. N. N. at Berlin, Vienna, Trieste,

Commissioners, the House of Lords Office, the House of ComVenice, Rome, Naples.

mons Office, the Copyhold and Tithe Commission, Ecclesiastical

Commission, Emigration Office, Lunacy Commission, Mint,

Londres, le 4 Mars, 1863. National Debt Office, Patent Office, Paymaster-General's, Record Messieurs,

Office, and General Registry Office. La présente lettre circulaire de recommandation et de crédit Specimens of some of the examination papers that might be vous sera remise par James Muirhead, Esq., d'Edimbourg, set to candidates for offices in this group are annexed, in con* auquel nous vous prions de vouloir bien faire un accueil obli- tinuance of the plan announced at the beginning of the series. geant, et lui procurer en même temps la possibilité de se The importance of dealing with these papers in the manner mettre en relation d'affaires avec les grands propriétaires de there suggested cannot be exaggerated. They should be not votre pays. Mr. Muirhead appartient à une des plus riches only worked out as carefully as if the student were actually familles de l'Écosse, dont les terres prospèrent sous sa direction. about to stake his career on the solution of them, but caro Vous nous obligerez infiniment, Messieurs, si vous pouvez aussi should be taken to secure their correction by some able person. contribuer aux agréments d'un séjour de quelques semaines Such a person might also be induced to frame other papers que la famille de notre recommandé fera dans votre capitale, from the specimens, and these fresh papers should be indetandis que Mr. Muirhead lui-même visitera les terres voisines fatigably worked out. Where no such friend is at hand, the de la métropole.

best way for a student is to arrange to work the papers conQuant aux fonds dont Mr. Muirhead aura besoin, nous l'accré. jointly with some one else in his own position; that is to say, ditons chez vous pour une somme totale de £5,000 st. (nous each student should work out the questions to the best of his disons cinq mille livres sterling), qu'il vous plaira de lui payer, en ability, and then compare his answers with those of his fellow. marquant sur le dos de cette lettre chacune des sommes qu'il Should they, having worked thus independently, arrive at the aura touchées jusqu'à épuisement de son crédit. Vous voudrez same result, the probability is strong in favour of the answer bien chaque fois ajouter à ces paiements votre commission de being right; should they differ, there will be good exercise for banque et tous les autres frais, en vous remboursant sur nous au both in finding out which of them is wrong. There can be meilleur cours possible et à l'échéance qui conviendra aux usages little difficulty in working out the arithmetic papers by this de votre place.

method. A little more trouble may be occasioned by verifying En vous assurant, Messieurs, que le meilleur accueil sera tou historical and geographical and such-like matters; but there * jours préparé à vos traites pour les paiements que vous ferez à | will be found in the various manuals which have been published,

and which are well known, sufficient information to meet the 5. Geography, requirements of all.

6. History of England.

7. Latin. 1.-BRITISH MUSEUM.

8. French, or another Modern Language. This office, at the Museum in Great Russell Street, is charged II. SUPPLEMENTARY CLERKS. with carrying out the administrative detail of the duties of the 1. Handwriting and Orthography, trustees for the Museum. Patronage in the three principal 2. Copying into Forms and Registers. trustees, who are the Primate, the Lord Chancellor, and the 3. Indexing. Speaker of the House of Commons. Limits of age of candi. 4. Arithmetic (including Vulgar and Decimal Fractious). dates-assistants, 18 to 25; attendants, 18 to 40. The at

5. English Composition. tendants, whose duties are in the library and reading-room, and III, OFFICE-KEEPER, MESSENGER, AND PORTER. who bring books to readers upon requisitions being made for

1. Handwriting and Orthography, them, are examined in

2. Arithmetic (elementary). 1. Writing from Dictation.

Salaries :---Supplementary clerks, £80 to £200, by £5 a years, 2. Reading.

junior clerks, £100 to £250, by £10 a year; senior clerks, £300 3. Elementary Arithmetic.

to £500, by £15 a year; messengers, £60 to £80, by £2 10s. Assistants (the clerks are so called) are examined in

a year. Prizes of the office-Registrarship, with £600; secreI. ASSISTANTS.

taryship, with £800. 1. Writing from Dictation.

4. HOUSES OF PARLIAMENT. 2. Arithmetic (elementary).

The educational tests in the offices of the two Houses are the 3. English Composition.

same. The work done consists in executing all the detail of 4. Précis.

office work connected with either House, and it is light or heavy 5. Geography. 6. British History.

according as Parliament is in session or vacation. Patronage 7. Two Languages besides Engiish, one of which must be either

in offices of the Commons House is with the Speaker for the Greek or Latin.

Speaker's department; with the Clerk of the House for his; II. JUNIOR ASSISTANTS.

with the Serjeant-at-Arms for his. Appointments in offices of 1. Writing from Dictation,

the House of Lords are in the gift of the Lord Chancellor, the 2. Arithmetic (elementary).

Clerk of the Parliaments, and the Usher of the Black Rod 3. Précis.

Limits of age for admission, 19 to 25. 4. Translation from one Ancient or Modern Foreign Language.

I, CLERKS, TEMPORARY CLERES, AND SUPERNUMERARY CLERKS. Salaries :-Attendants, £60 to £120, by annual increments

1. Handwriting and Orthography.

2. The Power of Accurate Comparison of Copies with Origins of £3, £1, and £5, according to the class. Transcribers (who

3. Arithmetic (including Vulgar and Decimal Fractions). are examined in the English language and two foreign lan

4. English Composition. guages, in addition to the subjects prescribed for attendants) 5. History of England, and of the Constitution. receive £90 to £150 a year, by annual increments of £10. 6. Latin or French. Assistants receive £150 to £400 a year, by annual increments 7. (For COMMITTEE CLERKS) the Elements of the Law of Exis. of £10, £15, or £20, according to class. The prize of the office

dence. is the principal librarianship, to which is added the office of II. ASSISTANT TO ACCOUNTANT, secretary, bringing to the holder, in addition to a good position 1. Handwriting and Orthography. in the literary, scientific, and social world, a good house in the 2. Arithmetic (including Vulgar and Decimal Fractions), Museum and £1,200 a year.

3. English Composition.

4. Bookkeeping by Double Entry. 2.-THE CHARITY COMMISSION.

Salaries :-Junior clerks, £100 to £250, by £10 a year ; &SThis office is in York Street, St. James's Square. It is charged sistant clerks, £300 to £600, by £15 a year; senior clerks, with the detail of the duties thrown upon the Commissioners by £650 to £800, by £20 a year. The prizes are the principal the Act of Parliament which, in 1853, empowered them to deal clerkships, with salaries ranging from £850 to £1,000, by annual with lands and money left for charitable purposes in such a

increments of £25. way as would most thoroughly promote the objects of charity without reference to the special objects named in the bequests.

5. COPYHOLD, ENCLOSURE, AND TIThE COMMISSION. Patronage in the Commissioners. Office staff small. Third Office in St. James's Square. Commissioners assist in the class clerks get £90 to £150, by increase of £10 a year; second- enclosure and utilisation of waste lands; in the commutation class clerks get £160 to £280, by £15 a year; first-class clerks of tithes, and in arranging for payment of fines to lords of get £300 to £500, by £15 a year. Inspectors get £800 a year; manors. Their work is a purely artificial one, created by Acts and these appointments, with that of the secretary, worth £800 of Parliament to meet exigencies arising out of a change in 2 year, constitute the prizes of the office. Subjects of examina- English home policy. There is a great deal of purely profestion:

sional work for surveyors, architects, and lawyers, but the 1. Handwriting and Orthography.

clerical staff is small. Office patronage in the Commissioners. 2. Arithmetic (including Vulgar and Decimal Fractions).

Qualifications :3. English Composition.

I. CLERKS AND ASSISTANT RECORD KEEPERS. 4. Précis, 5, Two at least of the following:

1. Writing from Dictation.

2. Arithmetic (including Vulgar and Decimal Fractions).
(a) Latin or a Modern Foreign Language.

3. Correspondence.
(6) English History.
(c) Elementary Mathematics.

II. ARCHITECTURAL SURVEYOR.

The three subjects above, and 3.-Civil Service COMMISSION.

1. Designs of Structures and Preparation of Working Drawings

2. Measurement and Estimate of Builders' Work, In Cannon Row (formerly in Dean's Yard, Westminster).

3. Knowledge of Quality and Strength of Materials. Instituted in 1855 for the purpose of testing educational acquirements of candidates for the Civil Service. Clerical staff

III. PERMANENT DRAUGHTSMEN, Assistant SURVEYORS, AND AS

SISTANTS IN THE SURVEY DEPARTMENT. small. Patronage in the Commissioners, but the practice has

The three subjects prescribed for Clerks, and been in this office to throw the appointments open to competi. 1. Land Surveying. tion. Qualifications:

2. Plan Drawing. I. Clerks.

MESSENGERS are examined in Writing from Dictation and Ele1. Handwriting and Orthography.

mentary Arithmetic. 2. Arithmetic (including Vulgar and Decimal Fractions, Square Root, and the use of Logarithms).

Salaries :- Assistant record keepers, £80 to £150, by £5 a 3. English Composition.

year; assistant surveyors, £150 to £250, by £10 a year; second4. Précis involving the preparation and digest of tabular class clerks, £100 to £300, by £15 a year; first-class clerks, statements).

£300 to £500, by £20. Messengers get £60 to £80, by £2 109

stone of the Permian system; and then come plains of specimens collected by Count Strzelecki, along the

new red sandstone again, crowned by the escarpment eastern chain of Australia. Seeing the great similarity i

of the narrow strip of oolite, and by that of the cretaceous of the rocks of those two distant countries, I could rocks.

have little difficulty in drawing a parallel between This structure explains the course of the larger rivers. them; in doing which, I was naturally struck by the The principal watershed of the country is the tract of circumstance, that no gold' had yet been found' in the high ground extending from the north of Scotland far Australian ridge, which I termed in anticipation the into England; it is nearer to the west coast than to the Cordillera.' Impressed with the conviction that gold east, and therefore a much larger area of country is would, sooner or later, be found in the great British drained towards the east than towards the west. All the colony, I learned in 1846 that a specimen of the ore had larger rivers—with the exception of the Severn and its been discovered. I thereupon encouraged the unemtributaries--run into the German Ocean. The plains ployed miners of Cornwall to emigrate and dig for which occupy much of the middle and east of England gold, as they dug for tin in the gravel of their own are traversed by many tidal rivers; and from the nature district. These notices were, as far as I know, the of the country, the construction of canals has been a first published documents relating to Australian gold." comparatively easy task.

("Siluria.") II. Geological Distribution of Mineral Products.

Influence of Igneous Rocks in the Development of The modes of occurrence of minerals are in veins or Minerals in Veins. lodes, in regular or irregular beds, and in connection Mineral veins occur in igneous rocks as well as in with detrital matters. The consideration of the dis- aqueous rocks; but the intrusion of an igneous mass tribution of minerals will be treated' of under these among stratified deposits appears to have rendered their heads.

lodes richer than when conditions otherwise similar 1. Minerals in Veins.

obtain. Though it is difficult, in the present state of our know Gold is usually found in a quartz matrix, traversing ledge, to ascertain the laws regulating the deposit of palæozoic shales, chiefly those of the lower Silurian metalliferous matter, yet we are able, from general ob- epoch; and the auriferous lodes are frequently richest in servation of the geological structure of the earth, to say the vicinity of eruptive rocks. But the precious metal that here search may be made for minerals with some is found also in secondary rocks, such as those of Calihope of success, and that there exploration will be futile. fornia, Peru, etc., yet under circumstances exceptional to Hundreds of thousands of pounds have been expended the usual mode of association of gold. It appears that in the opening up of mineral districts; a large propor- where certain igneous eruptions, diorite especially, have tion of the sum utterly without profit.

penetrated the secondary strata, the latter have been Great Britain possesses a rich supply of minerals; we rendered auriferous for a limited distance only beyond have gold, silver, copper, lead, tin, zinc, antimony, nickel, the junction of the two rocks; and it is concluded that cobalt, bismuth, uranium, chromium, and other of the all secondary and tertiary deposits (except the auriferous rare metals, besides vast stores of iron; our coal beds detritus of the latter), not so specially affected, nerer are enormous, and earthy minerals are in great variety contain gold. and value. Statistics show that in Great Britain 350,000 The lodes carrying copper and tin in Cornwall and persons are actually engaged in mining operations, ex- Devon are richest about the junction of the killas (local clusive of quarries of all kinds, and that the produce is name for the slaty rocks of the Devonian formation in of the minimum annual value of £40,000,000.

this district), and the bosses of granite, and where they The lodes from which we derive our chief supply of are intersected by granitic dykes, termed elvans. It is metals are almost wholly confined to palæozoic rocks. worthy of remark that these metalliferous veins have Their occurrence may be sketched as follows:

a course or strike nearly east and west, and that these The Silurian formation in North Wales, in the Isle of phenomena are not confined to this area, but are exhibited Man, in Cumberland, in the lead hills of the south of in Saxony and elsewhere. Scotland, in parts of the Highlands, and in parts Other examples might be adduced, but these will of Ireland, contains metalliferous veins which yield suffice to show that intrusive rocks influence the metalgold, ores of copper, lead, silver, antimony, arsenic, and liferous richness of veins. zinc.

2. Bedded Mineral Deposits. The rocks of the Devonian formation in Devon and These include coal and iron ore of primary importance; Cornwall contain rich tin, copper, and lead lodes, and salt, gypsum, cement-stones, coprolites, iron-pyritės,

The carboniferous limestone in Derbyshire, ranging up bituminous shales, etc., of secondary value. to the north of England through Cumberland and the (a.) Coal occurs in many formations; it has been mined adjacent counties, also of the Mendips, and in Devon, for upwards of a hundred years at Brora, in Sutherlandis the chief depository of our lead ores. The same for- shire, in rocks of the colitic epoch, and is worked at mation contains large and rich deposits of hæmatite, Bovey Tracey, Devonshire, in Miocene beds. An anthraan ore of iron, as in the Forest of Dean and Somerset- cite occurs in the Devonian rocks in Spain; there are shire.

good workable coals of the age of the trias in Virginia Throughout the world, all the metalliferous lodes, and Hindostan, and of that of the lias in Hungary, and with some peculiar exceptions hereafter to be mentioned, less valuable coals, chiefly brown coals, occur in tertiary occur in stratified or the associated igneous rocks, not strata in Austria and other parts of Germany. But by newer than the Permian. It is thus that one generalisa- far the richest and largest supplies are drawn from the tion in the inquiry is arrived at, viz., that of the period carboniferous system in Great Britain, Belgium, United during which the lodes carrying our richer metals States, Nova Scotia, Australia, etc. were filled. Geology, like the more exact sciences, is In Great Britain no coal is found below carboniferous capable of advancing philosophical inductions to very strata, but it does occur in newer strata. In the midimportant results. Sir Roderick Murchison was en- land and south-western

counties of England, and in South abled in 1844, from the study of the gold-bearing tracts Wales, it is confined to the true coal measures underlain | in Russia, to predict the discovery of gold in Australia. by the millstone grit, locally called the " farewell rock,"

“ Having," writes Sir R. Murchison, "in the year because, in the language of the miner, when that rock is 1844, recently returned from the auriferous Ural Moun- reached, one bids farewell to the coal. But in the north tains, I had the advantage of examining the numerous of England and in Scotland workable coal seams occur

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