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Class 1. — MINING- AND MINERAL PRODUCTS.South Side—Areas S. 1 to S. 27.

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Model No. 1 represents a square mass of part of thecarboniferous, or mountain limestone strata. The littleand great limestone are both represented in this model,and the upper portion admits of being removed to showthe result of the extensive denudation which is so con-spicuous throughout the mining dales of the north ofEngland.

Model No. 2 represents the principal seams or beds ofcoal in the district east of the lead-mines of the north ofEngland, and situated, as regards geological sequence,above the mountain limestone strata.

Model No. 3 separates into four sections, in order toillustrate the displacement of strata by what is called the“ throw” of mineral veins, and the effects of denudation,which take away all surface indications of such displace-ment.

Model No. 4 is intended to illustrate the deceptiveappearances which are often presented at the surface bythe successive outcrop of the same beds of coal, lime-stone, or other strata. Conditions which require themost careful considerations in agriculture as well asmining, and which are especially deserving of attentionin the exploration of newly-discovered lands.

Model No. 5. Dislocations of strata require not onlyto be studied as regards the virtual section, but also asregards both horizontal and inclined planes. Whetherthe object of search be coal, limestone, or any othermember of a series of stratified rocks, it will be obvious,on examining the divisional plane of this model, that anadit or level may be driven upon this plane so as tointersect the desired stratum, or wholly avoid it.

Model .No. 6. This represents the intersection ofmineral veins and the disruption of strata caused thereby.The apparent shifting of a vein from its ordinary bearingis here shown to be only a result of ordinary mechanicaldisplacement.

Model No. 7 represents the surface denudation ofmineral veins, by which an apparent complexity of formis introduced, as regards the outline of the strata on thecurved contour of the surface.

Models 8 to 12 represent various conditions of strati-fied rocks in relation to their inclination, as comparedwith that of the surface, presenting conditions highlyexplanatory of facts which are of constant occurrence inmining, and of the first importance in geological surveys;but any detailed explanation of such phenomena wouldexceed the proper limits of this description.

III. Minerals associated with Lead Ores. —Theplans, sections, and models already described convey ageneral idea of the geological and mining conditions ofthe district from whence the specimens illustrative oflead-mining have been chiefly obtained. The remainderof the collection is arranged with a view to exhibit, first,the productions upon which the industry of the lead-miner has to be exercised; secondly, the processes bywhich he renders these productions fit for use; andthirdly, the results of his labour.

In considering the best manner of following out anyclassification of this natural order or arrangement, theexhibitor had in view to exhibit the first named in aseparate case, containing labelled specimens of the prin-cipal rocks, ores, and spars of Allendale and Alston, thenin a series of cases to show the various processes, andfinally, in another separate case, corresponding with thefirst to exhibit the finished products of lead and silver.As regards the second and third divisions of this arrange-ment no alteration was made ; but the first, now underdescription, was modified and altered under the followingcircumstances.

A number of agents and other parties interested inlead-mining, and chiefly residing in Alston Moor, wereanxious to send a collection of minerals collected fromlead-mines to the Exhibition, and a working, miner,Mr. Isaac Robinson, who was one of the parties, wasanxious to fit up this case in a manner corresponding tosome small collections which he had cemented together,and which had been much admired. As such a collec-tion formed, in point of fact, the essential feature of thefirst division, which had been contemplated, being speci-

mens of the minerals associated with lead, it was con-sidered, at a meeting of the parties concerned, that itshould be fitted up as proposed by Mr. Isaac Robinson,under the general superintendence and direction of theexhibitor and others. This was accordingly done, andthe case contains upwards of 2,000 specimens fittedtogether, not as a representation of any particular cavern,but grouped so as to present to view an example of almostevery mineral substance usually found in immediate con-nection with lead-ores. Some of the examples are in-teresting as ornamental spars. But spars are not aloneuseful as ornaments: they are partly used in the arts,and they also afford instructive indications in tracing thecourse of mineral veins. The whole of this case wascemented together by Mr. Isaac Robinson during theintervals of his ordinary hours of work.

IV. Examples of the various stages of Progressfrom the Mine to the Market. —This part of the col-lection is arranged in five cases, each containing sixboxes of one square foot each, being in all thirty boxes.

Fifteen of these boxes, in a line furthest from the frontedge of the counter, contain specimens of lead-miningfrom the excavation of the ore in the mine, and showingthe several stages of progress until ready to send to thesmelt-mill; and the other fifteen boxes, in a line nearestto the front of the counter, contain specimens of the oreas prepared for smelting, and its various stages of pro-gress, until manufactured into lead and the silver sepa-rated ; these finished products being contained in DivisionNo. 5 of this collection.

Case No. 1. Lead ore, as first separated from the veinin which it is found, and which in this state is called“ bouse” in the north of England lead-mines, and theplaces in which it is deposited at the surface are calledbouse teams. The depositing of the ore in these placesis greatly facilitated at Allenheads by the use of tippingframes, of a new construction, by Mr. W. G. Armstrong ,of the Elswick Engine Works, near Newcastle-on-Tyne .This example is from a “ flat” vein in Allenheads mines,in the great limestone, which rock forms the curiouslylaminated matrix with which the ore is intermixed. Theore and rock thus intermixed require to be separated, asis exhibited by the following examples. By a flat vein,or “ flatts,” is meant a horizontal extension of mineralsubstances to a considerable distance from the ordinaryvertical or steeply-inclined veins, which extend in themanner of fissures through the various beds of rockforming the district. The regular lamination of the oreis worthy of attention, as leading to speculations on theorigin of mineral veins; a subject of great practicalimportance. The example here shown is taken from apart of the “ flatt workings,” at a distance of about 20feet from the principal or nearly vertical part of the vein.

Case No. 2. “ Bouse,” or lead ore, as extracted fromthe vein, and showing an example of the curiouslypolished surface, which is a frequent characteristic ofveins, and which would appear at first sight to have beenvery carefully polished by artificial means, many of thesurfaces being sufficiently clear to reflect the images ofobjects in a tolerably definite form. The local name ofsuch bright and polished surfaces is il sUckcnsides andthe suggestion mentioned in the notice of the last speci-men, as to the value of scientific inquiry, applies with stillgreater force to the class of phenomena of which this isone of the most curious indications.

Case No. 3 contains a portion of the ordinary bouse,or ore, as newly worked from the vein, and much inter-mixed with the materials contained in Cases 1 and 2, aswell as with other earthy and sparry contents of veins.The produce of mineral veins varies from pure galena, ofwhich some pieces are shown, to masses of rock in spar,in which the ore is so thinly disseminated as not to repaythe trouble of extraction.

Case No. 4. The intermixed rocks and ores shown inthe preceding cases are first subjected to “ picking,” andthen to “ washing,” on a grate. The first of theseoperations separates from the general mass all such piecesof galena as are either not mixed with other substances,or which can be readily separated with a hammer on what