ON THE MANUFACTURE OF IRON. 745 
all the produce of the district on the spot. An analysis of the 3-feet and of 
the sulphur band will be found in the table hereafter given. The 3-feet is 
left in the workings to form the roof of the mine. The remainder of the seam 
varies from 8 to 10 feet in height, and indeed occasionally reaches 16 feet, or 
even more. In extracting the stone, headways are driven 9 feet wide and 
90 feet apart, from which, at intervals of 30 feet, boards are excavated 15 
feet wide. By this system “ pillars”’ are left 90,feet long by 30 feet wide. 
When the limits of the royalty are reached, or when, from any other cause, 
it is deemed necessary to work the pillars, they are removed, with something 
like a loss of 10 per cent. of their contents, so that in a good working, free 
from faults, the whole of the ironstone, within perhaps 73 per cent., can be 
brought away. 
The following tabulated results of analyses will give a correct idea of the 
component parts of the Main Cleveland Ironstone Seam, taken from that por- 
tion of the district where it is found in the greatest perfection :— 
Normanby, average 
of seam worked. Eston. Upleatham. 
IECOLONIGE OL IFON..: -c.5 22. 3S'OO aes eae NAG UZ wesw acct 37°07 
IBPEOMIEO OL IVON 222 5.2 .-. 2°60") aces okey ee GeO enews yO 
Protoxide of manganese... “TAT Saray eee 5 waco neEEE — 
Alumina et aA SIOZ. oan abig epOOn tame ececs YZRIeT 
LO 1 oy by 7 ry by. Seer | 
Magnesia sp 58 4:16" (anh scat ban es ea Oe 
LE DELL pen i Ral aia a Mocwelcr: “yb lees _— 
RURUPOUNGACIGL Os. 0... S22OOU ce Wa ohn eae aA 
SICH ee eaPalstcgriss: is <2.) T0736 ines Pascoe Oe OMnacsnes saeeekCrOn 
Sulphur {eo Ngee STAs ee aaed TT RIAS AT Tere — 
BMtOHOTIC ACIC xq o0- cas A Geer cad =e peers — 
PRORPUGIICACIC tse. ese | | LIGY “snc sven SROMEne! nen mnCLg 
LL USED Cg Ge alle erie re Fe ic ts ier sci — 
iter er ee ene NASA ack: ag aeeee ete e® aoa6 
97°27 100°41 99°90 
Metallic iron... PP Mer ee Le Ms CSE cock vino ye RAG 7 
Authorities .... ... ...Clarence Lab. Dick. Geol. Survey. Crowder. 
Normanby 3 ft. Sulphur 
Skelton. Skelton. roof. band. 
Protoxide of iron .......00.4. AE*GQ) neds ee AA°3 Te inanv ay 33°86) vaccse, 19°97 
Peroxide Of 17011 .....cccses = —— seven =" een et fn 47a eaten _ = 
Protoxide of manganese ... °75 seeese = Ceces oe GOh seed — 
FAT GINITIAS osedeecadsssissstaeses SiGTe coscen TI6Gi sevdes Grigg sessee 8°47 
WPMIO NMG. Siasy caneSeecaxshs osicae Gi33h sche. 4266 ike HPS SZ keseseayy G49 
Magnesia .scsscsecvcsenaceeees BSG lar «oes 2°38 endses 378A. sacs « 1'07 
MOHAB a aac getp re dd<< das cn sace's a= fee opty. So. eeecaa — serene 
Carbonic acid ......ses0eees.. 21°30 a | QTD ven sansa DOtOO) arene — 
includes water. 
Biltemeigeadebiees s- o0c2ccceed debt YO°SAY wogens 7GGr date ERI2A) becdeds 10'94. 
: 28°37* 
Rl pa tacccthsttea-ar-t eran, eee LOR osc 40 13 
Sulphuric acid ..............5 eee —— tosis —— semen — 
Phosphoric acid ...........- Pe oe A MSO camves oy eas —- 
Orpanitig: to. sesites es sasee0s Shane OP ene ens oie — 
Water cesses Serehecee satin ==" ‘anges eee 3°69 wees 13°20 
9°78 100'71 “60 ‘ 
Metallic iron ............s0004. aeG seo QAA Zh cas ae 2666 pe? v Es 
Authorities ...... Clarence Clarence Clarence Clarence 
Lab. Lab. Lab. Lab. 
The relationship existing among the earthy constituents of the Cleveland 
* Sulphur and iron, as bisulphide of iron—28°37 sulphur, 24°82 iron. 
