May 27, 1909J 



NA rURE 



Ml 



but is often useful as an illustration, and, without 

 prussing the resemblance too far, the organisation of 

 the Himalayan mountains may be compared to that 

 of .1 i;reat army, composed of many thousands of 

 individual soldiers, grouped in regiments, these, again, 

 in brigades and divisions, each having a separate 

 indiviikiality ; but the individuality of the soldier 

 differs from that of the regiment to which he belongs; 

 this, again, merges in the individuality of the brigade, 

 and the whole in that of the army. So with moun- 

 tains, the peaks may be grouped into massifs, these 

 into ranges, a series of which may form a great 

 chain or system like that of the Himalayas or the 

 Andes; but just as the brigades of an army are not 

 each extended along the whole front, so the ranges 

 do not extend along the whole length of the system. 

 Each in turn comes to an end, and the chain is taken 

 up by another, not as a direct continuation, but over- 

 lapping the end, so that the direction of the in- 

 dividual ranges is oblique to that of the system as 

 a whole. Any other arrangement would probably be 

 as physically impossible, with material such as that 

 of which the earth's crust is composed, as the mar- 



of lofty, snow-clad peaks, misleading if meant as 

 a name of a mountain range or system. Range 

 it is not, for Dr. Hedin is clear enough on this point, 

 as he repeatedly speaks of the separate ranges of 

 which it is composed, and gives their number as no 

 less than ten ; mountain system it equally is not, 

 having no separate existence. If a new name is 

 required at all, it must be one which will unite these 

 ranges with the Himalayas, not one which suggests 

 a separation, for the valleys of the Sanpo and Indus 

 no more separate the mountains on either side of 

 them than, on a smaller scale, are the analogous 

 valleys of the Rhone and the Rhine a reason for 

 splitting up the unity of the Alps. 



This criticism must not be taken as in any way a 

 disparagement of Dr. Hedin's achievements; there 

 can be but one opinion of the brilliance of his ex- 

 ploration and of the courage and determination with 

 which he overcame the obstacles in his way. The 

 publication of a detailed account of his travels will 

 necessarily form an important addition to our know- 

 ledge of central Asia, but the fullest recognition of 

 its importance does not involve an acceptance of Dr. 



shalling of an army in brigades or divisions drawn 

 up in lines extending along the whole length of the 

 front would be militarily impracticable. 



This interpretation of the orography of the Hima- 

 layas is borne out by such maps as we possess, and 

 especially by those maps attached to Messrs. Burrard 

 and Hayden's valuable sketch of the Himalayas, 

 which exhibit the facts, rather than Colonel Burrard's 

 interpretation. In these it will be seen that the high 

 peaks of the Himalayas do not form a single range, 

 but rather a band crossed obliquely by a series of 

 ranges, and if we are to group these individual ranges 

 into a single system, and to include in it the lesser 

 ranges lying to the north and south, there is no 

 reason, geographical or geological, for separating it 

 from the mountains of southern Tibet and the 

 northern territories of Cashmere. Structurallv and 

 orographically, the whole of the mountains between 

 the Indian plains and the lake region of central 

 Tibet belong to one great system, and the term 

 which Dr. Hedin wishes to introduce is either 

 unnecessary or misleading ; needless if it merely 

 indicates the country north of the first belt 



NO. 2065, vor.. So] 



Hedin's deductions, nor does a difference of opinion 

 in regard to them imply any question of the accuracy 

 of his observations. 



THE TEACHING OF GEOMETRY. 



'T'HE circular recently issued by the Board of 

 J- Education on " The Teaching of Geometry and 

 Graphic Algebra " is an important document from 

 at least two points of view. First, it has a very 

 considerable educational value in indicating the suc- 

 cessive steps or stages which it is proper for a teacher 

 to take, and, secondly, it supplies information as to 

 the way in which the changes, introduced mainly by 

 the Mathematical Association, have worked out. 

 Those who have advocated the reformation of the 

 teaching of geometry will be glad to know that the 

 verdict of the Board of Education is favourable. "It 

 should be stated at the outset that the general effect 

 has been beneficial." 



The reformers had most serious difficulties to face, 

 the greatest, perhaps, being the almost divine authority 



