220 Professor Hoffmann on the Writings of Baron Humboldt. 
account of the probably necessary connection of the focus of 
voleanos with the sea. The essay in which this remarkable 
phenomenon is described forms a portion of a collection, en- 
titled Fragmens de Geologie et de Climatologie Asiatiques. 
1831. 2 vols. It is also published in Poggendorff’s Anna- 
len, vol. xviii. p. 1, and entitled, ‘On the Mountain-chains 
and Volcanos of Central Asia” (Ueber die Bergketten und 
Vulkane von Inner-Asien.) 
We must here necessarily pass over all that Humboldt has 
contributed to our knowledge of the physical relations of our 
globe, to geography, meteorology, and the geographical dis- 
tribution of plants, of which last subject he has himself created 
several new branches.* 
* From Hoffmann’s Hinterlassene Werke. We think it may be useful for our 
readersto subjoina list of thepapers by Humboldt which have appeared in this 
Journal, many of which are specially referred to in the above summary of 
his geognostical investigations. Edinburgh Philosophical Journal :—On the 
Earthquake which destroyed the Town of Caraccas, vol. i. p. 272; on the 
Detonating Mud of South America, &c., vol. i. p. 423, and 424; Account of 
Electrical Eels, vol. ii. p. 242; on Isothermal Lines, and the Distribution of 
Heat over the Globe, vol. iii. p. 1 and 256, vol. iv. p. 23 and 262, and vol. vy. 
p. 28; on the Great Cavern of the Guacharo, vol. iii. p. 83; on the Tem- 
perature of the Mines of South America, vol. iii. p. 286; on the Distribution 
of Vegetable Forms, vol. vi. p. 273, and vol. vii. p. 47; on Fossil Organic 
Remains, vol. ix. p. 20; on Rock Formations, vol. x. p. 40 and 224; on the 
Horary Variations of the Barometer under the Tropics, vol. xiv. p. 328. 
Edinburgh New Philosophical Journal:—On the Principal Causes of the 
Difference of Temperature on the Globe, vol. iy. p. 329; on the Structure 
and Action of Volcanos ‘in different Regions of the Earth, vol. v. p. 222; 
Discourse delivered at the Extraordinary Meeting of the Imperial Academy 
of Sciences of St Petersburg, vol. ix. p. 97; on the Mountain-chains and 
Volcanos of Central Asia (with a map), vol. xi. p. 227, and vol. xii. p. 145; 
on Two Attempts to ascend Chimborazo, yol xxiii. p. 291,--Epir. 
