223
the engraving, and the system of etching, by horizontallines, which prevents all confusion to the eye, and givesthe best idea of the form of the ground.*
The Council Medal is granted to the Depot dk laGuerre (804, p. 1219), in Paris , for the scientific bodyemployed in executing the land map of France .
Austria has presented maps of Italy and of the Duchy ofAustria, equal to the best of England and France . In-deed, the maps of Italy were undertaken by the French ■when they were possessors of that peninsula. j
The Council Medal is granted to the Military Geo- !<su ai*h ical Institute (303, p. 1028, Austria), Vienna , iwhich presents the maps. j
Geological Maps . —Some years ago, Mr. Greenough, a :distinguished geologist, executed a geological map of ,England upon a scale not larger than that of France . |Sir Henry l)e la Beche had the courage to undertake a ]new geological map upon the great scale of an inch per imile. This large size rendered it possible to add scientific !information in the ordinary map, to present in great de- \tail the nature of the stratifications, to apply his map toagricultural, metallurgical, and mining studies, and togive the delineation of the metalliferous and other veins.Sir Henry De la Beebe, alone, executed the geologicalmaps for Cornwall, Devonshire, and a part of Glamor-ganshire . Au official corps des mines was subsequentlycreated, under the direction of Sir Henry De la Beehe,with the name of “ Geological Survey,” which directedand continued the great geological survey of the threekingdoms. Sir Henry De la Beclie being the super-intendent of Jury I., fio whom this subject naturallybelongs, the adjudication on the merits of the geologicalmaps was transferred to Jury VIII. at our request.
The Council Medal is given to the Geological Sur-vey (159, Class I., p. 137), in honour of the excellenceof the work and of the staff of officers charged with theexecution of the map, under the direction of Sir HenryDe la Beclie.t
The geological map of France , a public undertaking,has been executed by the “ Corps National des Mines,”and we must add, principally, by two members of theInstitute of France , both General Inspectors of this body,MM. Dufrenoy and Elie de Beaumont. M. Dufrenoy,one of our French Jurors, was charged with the north-eastern part, and M. Elie de Beaumont with the south*western part of France . Both employed thirteen yearsin exploring the ground, and four years in the labour ofthe cabinet, as well as in the classification of more than30,000 specimens of minerals which they collected intheir local investigations, for which they travelled morethan 40,000 miles on foot.
The French geological map, executed on a scale of3 iinWith, is an excellent reduction of the great official mapof France. The Geological Society of London , consi-dering the great importance of such a scientific under-taking, granted their quinquennial Wollaston Medal toits authors.
The Council Medal is granted to the Ecole des Mines ,in liouour of the Corps National des Mines, whose en-gineer executed the map of France .
M. de Rexkmeuil. the ingenious foreman of theLithographic National Press of France , was the inventorof the excellent process for colouring maps. lie deservesthe Prize Medal now granted to him.
The principal geological maps were coloured by thehand, but the chef de la lithographic at the National Pressat Paris , has discovered so simple and ingenious a pro-ceeding for colouring with the press, that all is done nowby machine process. So perfect, indeed, is the operation,that, with a magnifying-glass, the colours are seen tofollow rigorously the lines forming the limits engraved
upon the map: and in no part do the colours exceed orremain behind that limit.
DUPIN, Reporter.
* Already 145 sheets are published, 03 are in the hands ofthe engravers, 52 more will conclude the work; so that itwill present 200 atlas sheets when complete.
f The “ Museum of Practical Geology” possesses richand unique mineral collections, furnished by the threekingdoms, and put in the most excellent order by Sir llcnryDe la Beche , who opened the Institution to the public shortlyafter the opening of the Great Exhibition .
APPENDIX.
The articles belonging to this Class, recently sent fromSweden , comprise—
1. A cast-iron shell-gun, of 8*9 inches calibre (Eng-lish ), and 9 feet G inches long, made on the constructionof Baron M. von Wahrksdorff, to load at the breech,and mounted on a carriage ami slide, also of cast iron,adapted to a casemate. The gun is in weight 9,071 lbs.Swedish (Victualie Vigt), or 81cwt. Oqr. 4lbs. English ,and is marked Aker, 1850, No. 4. The charge and weightof projectile are not stated, but the gun is understood tobe intended for spherical projectiles, and is not rifled.According to English proportions, the solid shot wouldweigh about 94 lbs., and the shell 70 lbs.
2. A cast-iron Swedish 0-poumler field-gnn, 5 feet5^ inches long, and in weight 850 lbs. Swedish , V. V.,equal to Tcwt. Oqr. 19lbs. English .
3. A Danish 6-pounder field-gun, also of cast iron,5 feet 3j inches long, and in weight 931 lbs. Swedish V. V., equal to 7 cwt. 3 qrs. 6 lbs. English .
Both these guns are from the iron-works of Aker, andbear the date of 1851.
4. Two models of 12-pomuler and 0-pounder field guns,with limbers and ammunition-boxes, Ac., complete, on ascale of one-eighth.
5. Lastly, the model of a 30-pounder long gun, on acarriage and slide of wood, for casemates, also on a scaleof one-eighth.
Shell-Gun. —The chief condition on which this guuhas been constructed (next to that of loading at thebreech), appears to be that its recoil should be verylimited, ami that it should not require to be run up. Itis accordingly mounted on a cast-iron carriage and slidewell suited to those conditions, and of ingenious con-struction, traversing on a pivot placed about 18 inches infront of the head of the slide, and therefore in the throatof the embrasure. The axis of the gun is four feet fromthe ground, and the total length of slide from its headto its extremity (being the distance it would occupy in acasemate), is rather less than 10 feet, or from the pivot11 feet 6 inches. The extreme breadth of carriage andslide is in front 2 feet 10^ inches, and in rear 3 feet2 inches.
The weight of the carriage is 5,215 lbs. Swedish V. V.,or 43 ewt. 2 qrs. 12 lbs. English , and that of the slide3,537 Swedish V. V., or 29 cwt. 2 qrs. Gibs. English .The gun and carnage together being 124cwt. 2qrs. lGlbs.English .
Though not requiring to he run up, the gun is not ona non-recoil principle, the slide being so constructed as toadmit of a motion of the gun and carriage when fired, ofabout 3 feet 6 inches, which at first is horizontal, andthen for about 3 feet on an inclination upwards of 12^°,by means of which the force of recoil (the weight movedbe G£ tons nearly) is gradually resisted and overcome.From the point to which the gun and carriage is thusraised, it descends by its own weight, and, after a fewinches horizontal motion, is received by an elasticcushion, formed of sheets of birch bark, placed vertically,and therefore perpendicularly to the direction of theforce, making a thickness of 9 inches. By this cushionall the remaining motion is absorbed. The angle of re-sistance of cast-iron on cast-iron being about 9}°, and themotion of the descent ending horizontally, the impressionon the cushion is rendered moderate, and all shock isavoided. The surfaces or hearing points, on which thecarriage rests upon the slide, are cylindric, of about3^ inches radius.
A carriage and slide of the same description as thatexhibited, but carrying a 02-pounder gun of BaronWahrendorlFs construction, was tried at Shoebury Ness,
* The subjects introduced in this Appendix arrived afterthe dispersion of the Jury of Class vni.