THE CARBONIFEROUS SYSTEM. 131 
almost always be satisfactorily correlated. ‘This will be so apparent on 
an examination of the sheets of grouped sections which accompany this 
volume, that no further argument will be needed to prove the unity and 
system which pervades our lower coal series. 
The general arrangement of the strata which form the Lower Coal 
Measures in Ohio will be seen at a glance by reference to the section 
given below: | 
SECTION OF THE LOWER COAL MEASURES OF OHIO. 
No. Strata. Feet. 
36 | Red and gray shales of Barren Measures................c.c00 senses coeces seceee coe ces Gs Waepect 
SOulmouUllwater sandstones often CONGIOMErALE (2...-02- ..---cacseee cesses ceecoeiees cae ceclss 0-50 
SAmGrayesmalewaltermatin oe witheNiOn 4 ccdtve.ssccemeseesecderetcctete aes tecerescleccneceente ey U-O0 
33 | Buff limestone, nodular and ferruginous (‘t‘ Mountain FoR Reel eees MOTO 
32 | Blackband iron ore, often replacing No. 32...... “3 icicssacasea| uly Weal: 
31 | Coal No. 7, “ Cambridge,” “Sheridan ” and “Grot” coal... HOREO EObAl| Ne aT. 
SYD) | TR RSACIEHY Boh codisH NS GHB He SRO NE RS OCC er RR on CoD i 3-0 
29 | Limestone, in eastern and SOUtHerN COUNTIES......... ce cco cee see see see cen cee cee cee 0-10 
POM Moin erat ESATA STOMC UE ttc tes cdlenccdaetah «csdee cacasefaevece dee sisnlectemen oseuse/enauceses 40-50 
27 | Coal 6a, *“* Norris” coal, sometimes a limestone over it.................0002-+0-|  O-6 
26 | Fire- clay .. dean Daves aden oa sania ee es ees caeee | ln MOE 
25 | Mahoning sandstone, “often conglomerate. LU Nes ta SAG DAM Geant a sa meee JOO) 
24 | Gray or black shale, alternating with No. 25.. se coatcconcs | O=OU 
23 | Coal No. 6, “ Straitsville, LS Big vein” and “ Uppe T - Freeport coal ...... 3-12 
22! Fire-clay .. BA soon, Ow) 
| Limestone, ““Breeport, 37 Op “White” limestone, i in eastern counties...... 2-8 
21 | Gray or black shale, with nodular iron ore at base .. 25-50 
20.| Coal No. 5, “Mineral Point,” ‘ Newbery: Fe eeeet >< Lower Freeport” 
coal . aes Pere SrA Nua Mn aan Es My) 
19 | Fire- -clay, ‘often non- plastic iidiex cellent alate sd. ul aude cols ts 3-6 
Smo lnaleramde Sand stom ebrnceacescceroniocseensseenaced ceesiceseclendoeaee eowsisuiscalsdcersitnctesss 20-40 
17 | Limestone, ‘ Putnam Hill,” or ‘Gray Ferriferous” of southern Ohio.....; 2-8 
16 | Coal N 0. 4, often double, ‘‘ Flint Ridge cannel,” “Strip vein,” “‘ Kittan- : 
TOWN ONER I aoe Ree ea ein aeeies saclitesareretecdGioncdel scan secuuseeuigasdced ssushawecnts 1- 
Fire- clay MRS Ms e sce ee Onesie etatsurectlercnesded aus elioweiccutevecinsoddgeclovenedesaieeasesass 2-12 
14 | Shale and sandstone, sometimes containing Coal 36......... 2200. seesee coeeeeees 20-90 
13 | Limestone, with iron ore, blue, often cherty ‘“‘ Ferriferous” of Pennsy]l- 
VWNIDUIB) cooga6ags' doobado0s Hooked ocabdoo0\odo0Gn6e LEb3CKECK FEOCEAI00 COONGHENG CHOEDE Ge DARDEN ES noes 2-6 
(OR mCoaleNousslowerlimestones)y Creek: Ve 22.120. .ccccsesselaoosesecseosccecierera= 1-4 
11 | Fire-clay, extensively used for pottery EEE Ra ON Mcitacl tsa eathe sbeed weasel ete We sont 5-15 
10 | Shale and sandstone, ‘“ Tionesta ”’ sandstone Bees cis dusedd at's dies avcltlicuesueeesese 30-50 
9 | Coal No. 2, generally thin, ““Strawbridge” coal ...............02.ceeccs coooseesees 1-5 
Bj IP TWAS=GIlIN 206. c50000:000000.6oG008 000006 068008 608030 Goeque docob5 Hodbad dueccrbd0De. Londen Idd Ane ica 1-3 
MES Wiel] CR eee eet ere eiene Cea costnecle veces in (oct neeGinaees as nassuas\ovee seine stivwstiovseee seems ccs 20-50 
@ |, Ilassribioin, SaNTGISKOTEKS) &55.4080 coodes. cueqne cob5dsadobea 666056 :500066000000 G05d060H0 G59680008.000600 20-80 
5 || Gieany SIMeIIG 4.0086 eddonn wagers soodba cegkeb OGbd BONG NOLOGY bor pbOdey aaa uECOU COnCOKoT CoOnddI00 DoEHD 5-40 
ABiEeCoalsNomiacoBrier Elly a aMiassillon sa wacksom 7 \COale as. ..ceseesaccceenc ss 3-6 
3 |) IBTTRB=GIEIZ ccosedccoldnadeblecdonbesd “GoOUGEORH bo6d54 HucdoooKuBTdads DE BdaDlodobEd Kooc0G00 bocouD aoTaDOnGE 3-9 
BD!) SINCISWOINS ATC! SOE \s.0066 060000.006900.000808 04000" 006000008 500000 060006 c00K00 006850 GonEBONDIs 10-50 
Th 1} (Comm@alorenverBi® ° S6ocen 60de0d0d0 6800080. ONG Ebe COCUBL SR OBDESCE EI CRONE LaWedsetenee eve cucveteen reliant aetiess 
The following notes on the lower group of coals and some of the strata 
associated with them will not be without interest and value to those 
who desire to acquaint themselves with our coal geology : 
