166 oeoloon \f report. |1i262, 263 



In regard to the manner of working these deposits, I ought to .say in general, 

 that the roof of Uio mines will usually require to be supported, more or less, 

 by wood-work : being rarely formed of materials sufficiently rigid to support 

 themselves when spanning an}- considerable excavation; in beds of notable 

 thickness and solidity, it will be found advantageous to allow a part of the lig- 

 nite stratum to remain above, so as to impart additional firmness to the roof — 

 which, Avith the aid of pillars left standing on the sides, as practiced in coal 

 mining, will often enable us to dispense « tderable part of the wood- 



work. In some the outcropping bed may be worked like a quarry, but 



more generally, galleries and chambers will be necessary — driven either from 

 tho hillside or from a shaft. Attention must be given to the ventilation of 

 these mines, for both the explosive •fin-damp," as well as, more frequently, 

 *he '•choke-damp, (which is very commonly perceived at the bottom of wells 

 sunk in the lignitic formation), are to be looked for in them. 



262. In Tippah county, lignite is hound on S. 29, T. 3, R 3 E., 



at Squire Street's. The bed occurs in a ravine, between two steep 

 hilkides ; its thickness and quality, I have had no opportunity of 

 observing. It was said to burn well in the lire-place and forge. 



According to Prof. Wailes, a deposit of lignite exists on Snow 

 Creek, S. 7, T. 4, R. 1 E., Tippah county, about 7 miles S. of Salem. 



According to L. Harper, lignite exists in Marshall and Lafayette 

 counties, on the Tallahatchie River. I have not, however, myself 

 observed, or seen any specimens from that region, save black lignitic 

 clays, with small seams of lignite. These are abundant in the 

 Coruersville region, and is quite likely that lignite beds may exist 

 there also. Lignite beds probably occur in R. 1 E., TT. 9 and 10, 

 S. W. Pontotoc, as they do in the adjoining portions of Lafayette, 

 but I have no definite knowledge of outcrops any where in Pontotoc 

 county. 



263. Lignite appears, more or less, all along the Yokeney-Patafa 

 River, and on many of its tributaries, in Lafayette county. 



According to information given to L. Harper by Mr. W. J. 

 Vineyard, lignite crops otttat the spring of Union (Baptist) Church. 

 3 1, T. 10, k 1 W. The bed is said to be 8 feet in thickness.— 

 The bulk of the specimen in the Survey collection is grayish black, 

 of a dull fracture, not very hard, easily crushed, and whitish on 

 the cleavage planes ; it contains thin layers, however, of black, 

 shining "pitch-coal." Burns with a bright flame, and leaves 24.2 

 per cent, of ash, of a faint reddish-yellow tint. — The amount of ash 

 is large, and if the whole mass were of the same character (which 

 is not likely) it would not bear transportation to a great distance. 



It is the same bed probably, which is met with in numerous 

 localities in townships 10, Ranges 1 and 2 VV., Lafayette county, 

 its thickness varying from 5 to 12 feet ; there seem to he, however, 

 several minor beds above it, which were observed by Mr. Ward, 

 S. 22, T. 10, R. 2 W. — one 5 inches, another a foot in thickness. 

 The main bed crops out in branches in Mr. Ward's neighborhood ; 

 at Mr. Kirkwood's, S. 25 ?, a stratum 8 feet thick was struck in a 

 well at 50 feet; at Mr. Greager's, on S. 14, the thickness of the 

 bed was greater by several feet. It crops out, with a visible 



