Notice of the Wonders of Geology. 3 
We have, in no degree, fallen off in our admiration of this 
beautiful work.* In our remarks upon the first edition, we 
stated our views of the different modes of treating geology, as 
regards the order. That which Dr. Mantell has followed in 
all the editions of the Wonders, is from the gravel down through 
the alluvial and diluvial, the tertiary, the secondary and transi- 
tion to the metamorphic and the primary rocks, the internal 
fires and the volcanoes. This order has its advantages, but it 
requires inconvenient anticipations: An individual who has tri- 
ed, in courses of lectures, every order that can well be proposed, 
has come to the conclusion, that the better mode is to begin 
with the actual voleanic vents—the living fires of our world, con- 
necting with them the dormant and extinct voleanoes—then to 
descend with the evidences of reguiarly increasing heat in all the 
rocks, until we reach the permanent internal fires—permanent 
in as much as they are never entirely extinguished, although they 
may fluctuate in position and intensit 
In this manner we arrive, by an inteigints process, at the 
region of the primary or unstratified rocks, now universally ad- 
mitted to be of igneous origin, and thus we establish the domin- 
ion of fire, all the doctrines connected with which are intelligible 
and credible, and of commanding and pervading energy, among 
the dynamics of the planet. We are also thus furnished with the 
key to the intrusions of the igneous rocks among all the other 
classes, and among each other, while the particular alterations 
among the various classes of rocks, by the action of ignited and 
melted masses, may be reserved for the time when those rocks 
shall be in turn examined. 
ocFrom the eranite; ve which: we th ive j d t, we nat- 
j f the strat ? estas erat 
the primary slates, as to whose alledged hic charac 
may thus be placed in a condition: to: Sout a sepa since othe 
* Prof. Silliman has had occasion during the late winter to make trial of its ca- 
pabilities for the instruction of large popular audiences in a public institution. 
The Lowell Institute at Boston, Mass., founded by the munificence of the late Mr. 
John Lowell, a native and citizen of that place, who died at Bombay, while on his 
gions) travels, and left an ample endowment for the support of popular lectures, 
well as instruction in exact details on morals and religion, science, ‘wales phy 
ae arts, &c. “A geological course was given during the late season, to two audien- 
ces, collectively amofinting to three thousand people. While Bakewell Pe other 
recommended to their perusal, the order of Dr. Mantell’s Wonders was 
followed in ihe lectures for the convenience of the audience. 
