24 POPULAR GEOLOGY. 



imbedded in soft liglit-coloured shale, but not nearly so good as 

 those found by Mr. Leyland on his first visit, which came out of 

 the matrix quite plump and free. I searched the cutting from the 

 top to the bottom but could not find the shells in situ. Those I 

 found, had been thrown out of the drain about half-way between the soft 

 bed coal and the grit. I visited the place afterwards several times, but 

 could find no better specimens and very few even of the imperfect ones. No 

 fossils belonging to this genus, have ever been found before in this 

 neighbourhood, nor have I ever seen any account of their being foiind 

 anywhere else, below the soft bed coal.* On accoimt of the numerous coal 

 and clay pits opened in this series of rocks, each particular bed is pretty 

 Avell known and good sections may be obtained in many places. The 

 only beds of coal worth working are the Hard and Soft bed coals, and 

 these are worked at Bradshaw, Catherine Slack, Shibden, North and 

 Southowram, and Elland All these bands of coal have a bed of seat clay 

 under them Avhich is extensively wrought to make fire-bricks, tiles, &c., 

 but that xinder the 3G yards band coal and middle band coal is considered 

 the best, and it is Avorked in different places along the edge of the hills 

 from the liowcans to Cinderhills and Elland. By far the most interesting 

 part of these lower coal measures to the geologist, is that enveloping the 

 hard bed coal. Over this bed of coal, there is a layer about three inches in 

 thickness, almost entirely composed of pectens and other marine shells, and 

 above that from three to five feet of shale containing round limestone balls 

 called " Baum pots." These "Baum pots" are generally coated with iron- 

 pyrites, and weigh fi'om 10 to 100 pounds and sometimes more. They 

 contain fossil shells such as Goniatites, Nautili, Pectens and Orthoceras, 

 some of them being literally one mass of fossils, but owing to the great 

 force required to bveak them open the shells are seldom got out perfect, 

 and often a few broken specimens are the only reward for many bruises 

 and hours of toil. The most perfect goniatites and nautili are found in 

 the shale, free or in very soft " baum pots." This bed of shale contains 

 many other fossil shells and the remains of fish, such as teeth, bones and 

 scales, which have a beautiful polish and are as black as ebony. The 

 floor of the Hard bed coal is composed of a pecidiar rock called Ganister, 

 unlike any other rock in the coal strata, but is found associated Avith the 

 mountain limestone rocks. This Hard bed coal has been traced, by 



• Air. Leyland has presented his specimens to the Halifax Museum, where they may 

 be seen and contrasted with others from Low-moor, Ac. 



