134 Reviews — Great Eruption of Str emboli. 



There is little doubt that, from the geological aspect, experiments 

 of these kinds, while of considerable theoretical interest, serve only 

 as a check to undue speculation. The transportation of debris by 

 rivers, and the degrading and aggrading of their beds are phenomena 

 which must be studied in the rivers themselves. 



Arthur Holmes. 



III. — Report on the Recent Great Eruption of the Yolcano 

 Stromboli. By Frank A. Perret. Smithsonian Report for 

 1912. Pub. 2200. pp. 285-9, pis. i-ix. 1913. 



IN 1907, and again in 1912, the normal activity of Stromboli was 

 broken by paroxysmal eruptions which indicate that this volcano 

 is sharing in the general increase of activity of the other 

 Mediterranean volcanoes. The 1907 eruption produced a crater 

 200 metres in diameter, and was marked by Strombolian explosions 

 in which large masses of incandescent plastic lava were ejected, 

 accompanied by clear vapours, alternating with Vulcanian explosions 

 in which dense black volutes of ash arose from the collapsing walls 

 as the lava column sank. The 1912 eruption increased the diameter 

 of the crater to 300 metres. The 1907 lava, which had partly 

 obstructed the conduit, was ejected in irregular solid blocks (olivine 

 basalt). Enormous quantities of ash were formed directly from 

 liquid lava, and scoriaceous lapilli of the same composition were also 

 ejected. Strombolian and Vulcanian explosions were even more 

 clearly denned than in 1907. The crater is now partly filled with 

 collapsed material from the cone, which tends to confine the gases 

 until they gather strength to break through and form an ash 

 cloud. The author's most interesting observation is based on the 

 hazardous experience of being completely enveloped in a cloud of 

 gas and ash proceeding directly from the crater during a paroxysmal 

 eruption. Since no distressing effects were produced, the conclusion 

 is inevitable that gases such as HC1, S0 2 , H 2 S, CO2, etc., which 

 are abundant during phases of minor activity, must be practically 

 absent during paroxysmal phases. Since 1907 the normal activity 

 of Stromboli has undergone a radical change which has deprived the 

 volcano of its former title, " The Lighthouse of the Mediterranean." 

 Indeed, so seriously is this the case that a lighthouse is to be erected 

 on Strombolicchio, a monolith of lava which rises from the sea near 

 Stromboli. 



IV. — An Introduction to the Geology of New South Wales. By 



C. A. Sussmilch, F.G.S. 8vo ; pp. xviii + 269, with 92 figures and 



folding coloured map. Sydney : Angus & Robertson, Ltd., 1914. 



Price 7s. 6d. net. 



TIIO anyone living in New South Wales, this introduction to its 



JL geology should be invaluable. Clearly written, excellently 



illustrated, and of convenient size, it forms a handbook that every 



New South Wales geologist should possess. It is not, however, lacking 



in points of general interest to the casual reader outside the State. 



To mention only a few of these points — the occurrence of glacial 



conditions in the Cambrian (p. 17) and their recurrence in the 



