58 NATURAL SCIENCE [JuLy 
in the neighbourhood of Budapest, and the spheroidal weathering of 
dolerite at North Queensferry, given on p. 455. 
The second volume opens with the Great Whin Sill, which is pro- 
visionally referred to the Carboniferous period. A considerable series 
of volcanoes is then included as Permian, or possibly Triassic, on the 
ground that “there is usually ample proof that the strata in question 
[associated with them] are much later than the Coal-measures, while 
their geological position and lithological characters link them with 
the undoubted Permian series of the north-east of England.” The 
best known mass placed in this group is the upper portion of Arthur’s 
Seat, Edinburgh, which, the author maintains, is independent of the 
older and true Carboniferous series. He thus supports Maclaren’s 
view of 1839, in opposition to its subsequent revision by its author, 
and to the well-known paper by Prof. Judd. 
Some exceedingly pretty mapping of the fragmental materials in 
a vent at Elie Harbour, Fife, is seen in Fig. 217; and the volcanic 
sections of this district are again finely illustrated by full-page photo- 
eraphs. The capping of Titterstone Clee, in Shropshire, is referred 
also to the Permian period. 
Then comes the great gap in our volcanic history, book viii. open- 
ing with Cainozoic times. The plateau-basalts are attributed to 
fissure-eruptions rather than to repeated flows from central vents ; 
and a very valuable chapter (pp. 260-269) supplies an account of such 
eruptions in recent times in Iceland. It is, however, pointed out that 
the tabular sheets are composed of the union of successive flows, one 
overlapping on the edges of another (p. 193); and the fact that cones 
are formed along the lines of fissure, each sending out its separate 
flows, is clearly brought out on pp. 264 and 265. The absence of 
clear evidence of the connexion between our dykes and the superficial 
flows is very candidly stated (p. 268). The recognisable vents, such 
as Slemish in Antrim, and other well-known necks in the same 
county, indicate more normal conditions of eruption. 
While there is this difficulty in correlating the intrusive basalts 
with the lavas penetrated by them, we must also face the similar 
difficulty arising from the lack of continuity between the gabbro 
masses of Mull and Skye and the surrounding plateau-basalts. If the 
dykes form the orifices for the extrusion of the latter, why may not 
the heart of Skye have served equally as a great volcanic centre? In 
both cases, the intrusive rock presented to us is that which last consoli- 
dated in the vent ; its earlier and basal volcanic products may, how- 
ever, remain to us in the surrounding lavas. Surely the great core of 
Vesuvius is at this moment intrusive in the earlier lavas of its flanks. 
The author recognises some such argument on p. 348, but will not 
allow the site of the Cuillin Hills to have any direct relation to the 
existing surface-products (p. 362). Granting that a number of small 
vents suits the conditions recognised in Antrim, why may we not have 
traces of more centralised activity in Mull and Skye? The difference 
of opinion between the author and Prof. Judd on this point appears 
less fundamental, less to be insisted on, the more clearly we have laid 
before us the relations of the dykes and plateau-basalts from the 
fissure-eruption point of view. 
It can hardly be expected that Iveland should receive more detailed 
a ie 
