574 



NATURE 



[October 15, 1903 



reminds me of similar columns of ancient lava not un- 

 common among the trap rocks of the Deccan, and I enclose 

 a copy of a sketch I made of one of these in 1839, the re- 



markable similarity of which to the column on Mont Pelde 

 seems to be worthy of notice. A second similar column is 

 seen in the distance on the right. Richard Strachey. 



69 Lancaster Gate, W. 



"Lessons on Country Life." 



In your issue of September 24 you published a review of 

 " Lessons on Country Life," by Messrs. Buchanan and 

 Gregory, but may I ask, with all deference, if your reviewer 

 has not omitted to read an important part of this useful little 

 book? He refers to Mr. Buchanan's earlier works, "Country 

 Readers," Nos. i and 2, as " most excellent books for 

 children," but had he read the preface to the " Lessons " 

 he would have found that these were intended, not for 

 children, but for teachers. Your reviewer truly says : — 

 " Country life is a vast subject, so vast that no child can 

 learn during his school life even a fraction of the inform- 

 ation it may be desirable he should possess," and the same 

 remark may be equally well applied to teachers. This 

 book travels over much the same ground as " Reader " 

 No. I, but the matter is differently treated. In one case 

 simplicity of language is aimed at, in the other the inform- 

 ation is condensed, with a view, as it appears to me, of 

 leaving jt to the discretion of individual teachers to use 

 such lessons, or portions of each lesson, as are most suit- 

 able to their own districts. 



I do not wish wrongly to attribute ideas to the joint 

 authors, but I fancy their intention is to put before rural 

 teachers (many of whom have had little or no country train- 

 ing) as complete a summary as possible, taking it for 

 granted that they would be able to pick out and study the 

 essential parts. 



This series of agricultural Readers and Lessons will, I 

 think, do much to create a love of country life, may even 

 help to counteract the attractions of town life. Rural de- 

 population is one of the most serious problems of the day, 

 and if these books will assist, in only a small way, to arrest 

 this migration, I feel sure you will not detract from their 

 value by a few words which were probably due to a pardon- 

 able oversight. 



A. H. H. Matthews, Secretary. 



Central Chamber of Agriculture, Broad Sanctuary 

 Chambers, 20 Tothill Street, Westminster, S.W., 

 September 30. 



Mr. Matthews has hardly grasped the point of our 

 notice — that Messrs. Buchanan and Gregory's book 

 approaches the subject in the wrong spirit. The teacher is 

 provided with a mass of indifferently selected information 

 about farming matters, which he will pass on to his class 

 instead of trying to lead it to observe and reason on its 

 own account. The latter process is more difficult, but it 

 happens to be education. We have of late had only too 

 many occasions to deplore the " rural teachers with little 

 or no country training " who hand out " condensed in- 

 formation " from little books about the country. It is this 

 kind of instruction which offends both farmers and 

 educationists, and if Mr. Matthews imagines it is going 

 to counteract the attractions of town life and arrest rural 

 depopulation, we can only hope that on this occasion he 

 does not represent the opinion of the Central Chamber of 

 Agriculture. The Reviewer. 



NO. 1772, VOL. 68] 



CRATER LAKE IN URnGON.^ 

 'T^WENTY years ago, as Mr. Diller informs us, this 



-»■ picturesque record of a strange episode in 

 volcanic history was unknown to any but the Indians. 

 It is still not very accessible, for it lies in an un- 

 frequented region, deep set in the summit of the 

 Cascade Range, some sixty-five miles north of the 

 California _ line, but the United States Government, 

 " recognising its worth as an educational feature," has 

 already wisely secured it from the speculator and spoiler 

 by making it a national park. An area of two hundred 

 and fifty square miles is thus protected, of which we 

 find a description in the present memoir. The first 

 part, by Mr. Diller, deals with the geology and physical 

 history of the great volcano, named after a local 

 society Mount Mazama, which was shattered to form 

 Crater Lake, and the second, by Mr. Patton, discusses 

 the petrography of its rocks. It was virtually dis- 

 covered by Captain Dutton, by whom and by Mr. 

 Diller it has already been noticed; the U.S. Geological 

 Survey has also published a special map, but the story 

 is now completed in this excellently illustrated memoir. 

 The Cascade Range is largely, if not wholly, built 

 up of volcanic material. In Cretaceous times'^ it had 

 no existence, "there flowed the sea"; this retreated 

 during the Eocene, when vents opened in the Coast 

 Range region, possibly also, though that is not yet 

 quite certain, on the site of the Cascade. Here, how- 

 ever, volcanoes were in full activity during the 

 Miocene, and built up a large part of the Range, where 

 eruptions have continued almost to the present time. 

 Post-Glaclal outbursts occurred In some places, but 

 seem to have ceased before history began, though 

 hot springs and fumaroles show that the subterranean 

 hearths are not yet cold. Some of the peaks rise 

 above 10,000 feet, Mount Rainier even attaining 14,525 

 feet, and the surface of Crater Lake Is rather more 

 than 6200 feet above sea-level. It is an oval basin 

 between twenty and twenty-one square miles in area, 

 surrounded by cliffs which range from more than 500 

 to nearly 2000 feet in height, the ground falling more 

 gradually from their rim to the present upland level. 

 This great sheet of blue water, in places almost 2000 

 feet deep. Is Interrupted near its western margin by a 

 pyramidal rocky mass, called Wizard Island, itself 

 evidently a volcanic vent, and a study of the enclosing 

 walls of the great caldera proves them to be built up 

 in the usual way by ash-beds and lava-flows, dipping 

 outwards from its axis, and riven by occasional dykes. 

 The exterior slopes are dotted by parasitic cones, and 

 exhibit occasionally moraines and Glacial striae; they 

 are also furrowed by valleys, which in some cases 

 run up to and actually notch the edge of the cone, so 

 that they evidently cannot have been formed on Mount 

 Mazama as It now exists. They, like it, have been 

 truncated, and the bowl occupied by Crater Lake has 

 been formed by the destruction of a volcanic cone 

 which must once have risen some six thousand feet 

 above its present rim. Of this there can be no doubt ; 

 it is substantiated by numerous facts . cited In this 

 memoir, and we have only to study the geological 

 map which It contains to see that the present lava 

 streams are merely remnants of those discharged from 

 sources at a greater elevation and nearer the central 

 axis of the cone. 



But the precise mode In which the upper part of 

 the original Mount Mazama was destroyed, and 

 Crater Lake formed among its ruins, Is not quite so 

 certain. Two explanations are possible. All the 

 upper part of the mountain may have been hurled 

 In shattered fragments through the air by a series 



1 "The Geology and Petrography of Crater Lake. National Park." By 

 Joseph Silas Diller and Horace Bushnell Patton (U.S. Geological Survey). 

 Pp. 168. Plates i-xix. (Washington, 1902.) 



