324 Scientific Intelligence. 



hoochee river, Oclieesee, fifteen miles below the railroad bridge, 

 and again at Rock Bluff, two miles below Oclieesee. 



Section at Ocheesee, Fla. 



1. Argillaceous limestone, greenish yellow iu color, no fossils 



seen, ......... 10 feet. 



2. A purer, more granular limestone, creamy white and soft, 



resembling the "chimney rock" phase of the Vicksburg 

 group. Contains a lew obscure corals to water edge, 5 feet. 



Rock Bluff, about thirty feet high, is made up of strata of 

 limestone varying in purity as at Ocheesee. 



For this older member of the Miocene or newest member of the 

 Eocene White Limestone the writer suggests the provisional name, 

 Chattahoochee Group. The only fossils found were a large 

 Pecten about S"x3%" and an oyster resembling very closely our 

 living Ostrea Virginica. This group, estimated to be 250 feet 

 in thickness, differs materially in its lithologic characteristics 

 from any phase of the White Limestone yet observed in Ala- 

 bama or Mississippi. On the rich black loam, derived from 

 the disintegration of these slightly phosphatic limestones, the 

 unique Torreia taxifolia or "Stinking Cedar" is found grow- 

 ing. 



These outcrops at Chattahoochee, Ocheesee, Rock Bluff, and 

 Alum Bluff appear to be the western terminations of ridges 

 that extend eastward parallel to each other like gigantic ribs, 

 and between these ridges are found some of the richest " hum- 

 mock " lands in West Florida. 



On subsequent canoe trips down Conecuh and Pea rivers, 

 the writer failed to discover any Miocene deposits or any traces 

 of the Chattahoochee Group, so that it is believed that the 

 Chattahoochee river marks the western limit of undoubted 

 Miocene or at any rate Dana's Sumpter Epoch. 



University Ala., May 20, 1889. 



SCIENTIFIC INTELLIGENCE. 



I. Chemistry and Physics. 

 1. On the Heat of Combustion of Carbon. — Berthelot and 

 Petit have determined with great care the heat of combustion 

 of carbon in the three forms of charcoal, graphite and diamond. 

 Finely powdered wood charcoal was purified lor the purpose by 

 treating it successively with boiling hydrochloric and hydrofluoric 

 acids, then igniting it in a current of chlorine gas and finally 

 heating it to a high temperature in a Perrot furnace. On analy- 

 sis it was found to contain 99 34 per cent carbon and 0*66 per 

 cent of ash. The graphite was obtained by purifying the 



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