STATE GEOLOGIST. 93 
possible source of cement supply. Of such a character is the stone at 
Lisbon, Columbiana county, where it has been used as the basis of a 
“natural cement’ industry for years past. It is only 34 inches thick, 
occurring on the horizon of the lower Kittanning coal. It analyzes as 
follows: 
Per Cent. 
SHURE oy Birk SNES ES Ese SA Te aR Af OAC cI a 17.76 
PAUIUIIMIV epee eer t cp erNeee TTI Ripe 0h sa MD tae Sat test 7.94 
ETCH ONGC CR RGAAI Ns ype tiy eine. Sie ERED GIN Fare Fw So ies i aan Ie ose ui 1.86 
Cal CuunmIrcanrwon ace syn ewe let ls eae eerie ae Want ieeclie 66.25 
MereSIIN CAI DOMO so docncvscccgocenenooodaoudueus 2.82 
96.63 
Middle Kittanning.—A similar stone at Rodgers, in the same county, 
having a thickness of 4 feet 6 inches, has the following composition. It 
is obtained just under the middle Kittanning. 
. Per Cent. 
PSII Carel en Maairsulsis gain de Lyre Nal. COE Re INN olen hu seh on meee MEA, 25.44 
PAUIUTTYNITN epee eee oes ee Se tsee Bt pares, Sota Sh See cst So aM rs Pt 10.62 
HeTrricr Ox epee pein Pirate moa madine mtr Laat: NPM ye ah hun 2.34 
Caleimmercarbomatercesn waren hes net ek seh Siaicr se sts 55.59 
NieyeraveSinuNSN, GAA NCMVNIE. 656.0 oo 5 ooo b obo Koso os BAe 2.14 
96.13 
Both of these stones are won by mining. 
Freeport. —The Freeport limestone occurring on the horizon of the 
coal veins of that name are generally very impure, either being cherty, or 
clay like. No instance is known to the writers where this stone seems 
promising. 
Cambridge. —The Cambridge limestone, located approximately 100 
feet above the Freeport horizon, through a well marked horizon so far 
as regularity and persistence is concerned, is generally thin and worth- 
less for the present purpose. Like most of the coal measure limestones, 
its origin favored its occasional growth into relatively thick pockets and 
masses, but usually it is a thin layer, even degenerating into a stratum of 
bowlders separated by clay. At Cambridge, in Guernsey county, it is 
reported as of 8 feet thickness and as having been worked for lime. It 
is certainly not a wide or important formation for this use. 
At the head of Cannon’s Creek in Lawrence county, the Cambridge 
stone thickens up into a ledge of some 6 feet or so, quite cherty in 
character. A careful cross-section of this exposure analyzed as follows: 
mal Per Cent. 
Sil Campane a aierne ene iran: imate rimielasl Ma Li oN bes ba 8 38.00 
PANINTNA BAYS 5 0 Gch euler ae ee tet te ene ee ta 6.78 
LENGTEAIG: OD: IUGLEAG See seen see oad IRON ane Brag abe i ee 1.90 
CalcinmyearHomavenene ce vee ee eM ean ope aleme vee dee ve 50.60 
Meron estat DOMat Chweiriy eater nyek vin ern| ah ys ne rantee olen. 1.73 
99.01 
