316 The American Geologist. 
November, 1905 
"Finally the fact of 'consanguinity' among the igneous rocks of 
a petrographical province may be due as much to assimilation as to. 
differentiation." 
Mr. Daly has certainly added an important chapter to the liter- 
ature of the igneous rocks. The reviewer would suggest that prob- 
ably the hornblende gabbro of the Movie sill is itself a secondary 
rock, differing from true gabbro in the same direction as its con- 
tact phases differ from the body of the sill. The true gabbro of 
Minnesota was found to acquire hornblende and quartz, and often 
orthoclase, when it came into contact or contiguity with the acid 
sediments of the Animikie. It is quite possible and logical to sup- 
pose that a mass of true gabbro magma, in the lapse of time, lying 
beneath the earth's crust, or perhaps in contact with the lower 
part of the quartzytes discussed by Dr. Daly, would suffer such endo- 
morphic changes on a grand scale as to afford large quantities of 
hornblende-gabbro, and nothing else, in case of later intrusion into- 
the overlying sediments. n h . w 
La Montague Pelee et ses eruptions, par A Lacroix. Quarto, 650 
pages, 30 plates. Paris, 1904, 238 figures. 
This work is published by the Academy of Sciences, under the 
auspices of the ministers of public instruction and of the colonies. 
On opening the volume the reader is presented, in the frontis- 
piece, with a heliograph of perhaps the most wonderful natural 
scene ever photographed — the "burning cloud" of the 16th of De- 
cember, 1902, at the point of its arrival at the sea. Its hight, as it 
fades away and breaks into the air above was 4000 meters, or some- 
what more than 13,000 feet. Its wedge-shaped, boiling front seems 
to roll along on the earth, occupying the valley of the stream. At 
the sea-level its foot spurts out upon the water somewhat like the 
advance of the water of a tremendous comber after .it has broken 
upon the beach. Its higher portions are more advanced than its 
foot, but throughout its front its convoluted shape is marked and 
preserved, rendering it apparent that the great mass is as distinct 
from the atmospheric air as the dark thunder clouds of mid summer. 
It is only in the rear of the cloud that its outlines are confused 
and lost. Certainly no similar volcanic phenomenon was ever be- 
fore so truthfully and so vividly reproduced. Hovey and Heilprin 
have published numerous excellent views of these steam-ash clouds 
taken usually from near the crater and showing partially the won- 
derful convolutions they undergo. Lacroix's photo was taken from 
across the sea level, and includes the entire cloud from bottom to 
top. To the observer it must have presented a sublime and por- 
tentous aspect. Of the results of the devastation of such a death- 
dealing cloud, the destruction of St. Pierre, the author says: 
"J' ai rapporte une impression inoubliable, non seulement des 
phenomenes grandioses et passionnants auxquels j' ai assiste, mais 
encore des infortunes dont j' ai ete le temoin, des spectacles tragi- 
