VOLCANOES: 
WHAT THEY ARE AND WHAT THEY TEACH. 
By J. W. JUDD, 
Professor of Geology in the Royal School of Mines (London). 
With Ninety-six Illustrations. 12mo. Cloth, $2.00. 
‘‘The volume before us is one of the pleasantest science manuals we 
have read for some time.” — Atheneum. 
“Mr, Judd’s summary is so full and so concise, that it is almost im- 
possible to give a fair idea in a short review.”—Pall Mall Gazette. 
“Professor Judd discusses the nature of volcanic action, the internal 
structure of volcanic mountains, the distribution of voleanoes upon the 
surface of the globe, their activity in different periods of the earth’s exist- 
ence, the use of volcanoes in the economy of nature, the various theories 
that have been made to explain volcanic action. He has abbreviated in 
this volume a vast amount of information, which has a fascinating in- 
terest for many minds by reason of its relation to the past history and 
future destiny of this little bubble of earth upon which we sail through 
the infinite spaces of ether.”—New York Home Journal. 
“The book gives an exhaustive statement of the phenomena of volca- 
noes, and of the facts in the formation of mountain-chains, and relates a 
mass of interesting observations and facts, the results of patient and ex- 
tensive personal investigation and study, mostly in different places in 
Southern Europe, but not neglecting the world’s larger volcanoes in other 
regions.”—Hartford Times. 
“A fascinating example of patient observation, sound judgment, and 
acute reasoning. Under Professor Judd’s skillful treatment the volcano 
is forced not only to tell its own history, but also to solve a number of 
earth problems seemingly disconnected with it; and the story is told in 
strong, nervous language, and with an earnestness and subdued enthu- 
siasm that are delightfully stimulating.” —Boston Gazette. 
“Professor Judd first points out the errors in the old definition of a 
voleano. The volcanic hole is very often not on the summit, but on the 
side, sometimes at the base of the mountain or hill, and it sends forth 
steam rather than smoke, and the supposed raging flames are nothing 
more than the glowing light of a mass of molten material reflected from 
those vapor-clouds. So our old ignorance vanishes, and in this admirable ~ 
work the internal structure of voleanie mountains, the nature and prod- 
ucts of volcanic action, and the distribution of the materials’ rejected 
from volcanic vents, the succession of operations taking place at volcanic 
centers, are all very ably and clearly discussed.”"—-Philadelphia Times. 
“A succinct and excellent treatise on a very interesting subject.”— 
Philadelphia North American. 
For sale by all booksellers; or sent by mail, post-paid, on receipt of price. 
New York: D. APPLETON & CO., 1, 3, & 5 Bond Street. 
