292 BEPOBT — 1889. 



This fact is of value as another confirmation of the general depression 

 of the land in this district since Roman times. 



Excavations in Naples. — The continuation upwards of the funicular 

 railway tunnel at Monte Santo, Naples, fully confirms the suppositions 

 put forward in last year's Report in regard to the succession of the deposits 

 cut through. Overlying the great deposit of coarse breccia is a series 

 of pumices and ashes, with intervening vegetable soils and carbonised 

 branches, identical with the strata of the Parco Grifeo (Corso Vittorio 

 Emanuele), synclinal, showing that the Monte Santo grey tuff and breccia 

 occupies the same stratigraphical position as the blocks of piperno and 

 the remnants of a similar breccia met with all along the Corso V.B. at 

 Naples. The constant occurrence of the yellow Neapolitan tuff deposited 

 upon undoubtedly subaerial surfaces shows that that material is of sub- 

 aerial origin, and not submarine as some volcanologists suppose, because 

 a few marine shells occur in it : these may really be regarded simply as 

 ejected blocks of ' accidental ' origin. 



The work for the lower end of the tunnel has been suspended pending 

 a lawsuit, so that the relation of the Rione Amedeo tuff to the Cumana 

 Ry. trachytes is still unsettled. When this point is cleared up I shall 

 bave made out the stratigraphical order of the Campanian volcanoes — a 

 necessary foundation for their correct study. 



Returning to the extraordinary collection of rocks contained in the 

 Monte Santo, Soccavo and Pianura coarse breccia, I have an important 

 addition to make in the form of a block of brownish rock with rhombodo- 

 decahedra (?), having all the characters of decomposing haiiyne. The rock 

 is, in fact, indistinguishable from some of the haiiynopliyres of Monte 

 Vultura. As soon as the microscopic preparations of the rock are finished 

 (if these prove to be its true nature) it will be its first recorded occur- 

 rence amongst the Campanian volcanoes — a point of no small interest 

 when we remember that it is one of the earliest erupted materials of the 

 district, and its similar relationship to the leucitic rocks at Monte Vultura 

 and elsewhere. This block is from the Monte Santo funicular tunnel. 



The section exposed by this tunnel, so far as completed, is the 

 following : — 



Superficial dust and pumice beds (Astroni deposits and others ?), 15m. 



Compact yellow tuff of Naples (building stone of the town), 60m. or 

 more. 



Purplish grey or black dust, old vegetable soil, 0'20m. 



Passing down into fine grey dust, l'50m. 



Grey pumice and dust bed, 0'45m. 



Dust bed, grey at bottom, purple-grey or black at top, 0'35m. 



Parco Grifeo lapillo bed, with pumice, rather fresh, 0"45m. 



Four pumice beds, with their dust beds of grey colour, and semi- 

 compacted, about l'50m. 



Coarse incoherent breccia, composed of blocks up to half a cubic metre 

 in volume, consisting of vitreous piperno (of lava), porphyritic sanidine 

 obsidian (glassy trachyte), trachytes, dolerites, leucite lavas, haiiynophyre, 

 basalts, tuffs of different kinds — some solfatarised, others with organic 

 remains, besides many other varieties of rock.' The essential material is 



' On account of the great variety of rocks contained in this deposit a friend 

 suggested calling it ' the museum breccia,' and, wanting some designation for it, I 

 intend to so name it in future. 



