1848.] MURCHISON ON THE STRUCTURE OF THE ALPS. 293 



the coal seems to follow all the accidents and undulations of the sub- 

 jacent, so-called alberese, limestone on which it rests. Besides mytili 

 and plants, the tooth of a pachyderm has been found in this tertiary 

 coal, which M. Pomel has named lotherium. 



The other accumulations of this age occupy broken troughs through- 

 out the Tuscan and Roman Maremma, and those which I visited, 

 lie to the south of the rocky village of Monte Massi, where three 

 shafts have been opened and where the coal is much developed (see 

 fig. 38). Eruptive rocks, chiefly of serpentinous character, occupy 

 the summits, and on one of these the grotesque village of Monte 



]\fonte Y\&: 38 



N.N.E. Massi. ^ &* ^"* S.S.W. 



s rf? Debris, 1 2 3 



s. Serpentine breccia. ("3. Shale and coal, 



d.l Alberese. Miocene. < 2. My tilus limestone and coal. 



■6 



Miocene conglomerates and coal. 



Massi is perched. The rock is here a serpentinous breccia, classed 

 as " euphotide," which throws off vertical patches of alberese (d) on 

 all sides. But instead of the short interval which occurs at Monte 

 Bamboli between the surface of the alberese and the coal, we have, 

 first, a conglomerate of alberese, secondly, a thick mass of grey strati- 

 fied shale or clay, and thirdly, grits and small pebbly conglomerates, 

 with fragments of serpentine (ophiolite grit of Savi), on the last-men- 

 tioned of which the lowest bed of coal reposes. This succession is 

 obvious in descending from Monte Massi to the banks of the brook 

 on the S.S.W. , in which the natural outcrop of the lower coal is seen. 

 Even this lower coal (1) is not considered the same as that of Monte 

 Bamboli ; for after ascending through shale and grit, &c., another 

 seam occurs which is interlaced with and surmounted by the very same 

 mytilns limestone as that of Monte Bamboli (2), the whole dipping 

 away at about 25° to S.S.W. Then follows a considerable breadth of 

 argillaceous shale, the angle of inclination decreasing as the beds 

 advance into that broad valley which terminates in the mouth of the 

 Ombrone at Grossetto. Subordinate to this shale and claystone is 

 the third or great seam of coal (3), which is of considerable thick- 

 ness, and into which I descended by the new pits. Many portions 

 of the coal, whether judging from the eye or from its chemical ana- 

 lysis, diifer little from the inferior but useful qualities of British com- 

 bustible of the palaeozoic age. Unluckily, however, both Monte Massi 

 and Monte Bamboli are at some distance from the seaboard, and no 

 rail- or tram-roads having been yet constructed, all the expenditure 

 of the miners will be thrown away if public assistance be not given 

 to them*. The statistical data of these coal tracts, the great heat 

 experienced in the deep shafts at Monte Massi, the gases (not inflam- 



* I was accompanied to these tracts by M. Caillaud, the principal director of the 

 Leghorn Coal Company, and by M. Petiot, the inteUigent French engineer who has 

 directed the works. 



