4 6 



NA TURE 



{May 8, 1664 



I pass now to the neighbourhood of the St. Gothard. The 

 coarse gneiss, which is pierced by the northern entrance of the 

 great tunnel, ends abruptly at the Urnerloch. The basin of the 

 Urserenthal is excavated from satiny slates, with dark limestones, 

 very possibly of Jurassic age, and from some underlying rather 

 variable schists. ' The first rock visible on the eastern side as we 

 approach Andermatt is a schistose crystalline limestone, asso- 

 ciated with mica schists ; and a series of rather variable schists, 

 evidently very different from the coarse gneisses of the gorge 

 below, appears to cross the valley, and form the slopes leading 

 to the Oberalp Pass. These may be traced for some distance up 

 the Furka road above Realp, when they are abruptly succeeded 

 by the slaty group mentioned above. I am convinced that they 

 are much more ancient than the latter, being probably members 

 of the Lustrous Schist group, if not older. It is obvious that the 

 newer rocks are only a fragment of a loop of a huge fold, over 

 which on either hand the fragments of the enveloping older meta- 

 morphic rocks tower up in mountain peaks. On the ascent of the 

 St. Gothard Pass from Hospenthal a series of somewhat variable 

 micaceous schists continues till the top of the first step in the 

 ascent is reached, about 800 feet above the valley, when gneiss 

 sets in, generally rather coarse and sometimes very porphyritic, 

 occasionally interbanded with dark, rather friable mica schists. 

 The upper plateau of the pass consists of a porphyritic rock. 

 often called granite, but with a gneissose aspect and rather more 

 friable in character than the rock of the Wasen district. On the 

 first steep descent on the south side this rock appears to pass 

 into a normal coarse gneiss, occasionally banded with mica schist, 

 resembling that in a similar position on the northern Hank, which 

 is succeeded for a short space by a remarkably well-banded 

 gneiss. To this succeeds — it must be remembered that the 

 series is inverted in order — the great group of hornblendic and 

 garnetiferous mica schists, which continue along the Val Tremola 

 and the lower slopes of the mountain to the neighbourhood of 

 Airolo, where some calcareous rock occurs, being probably an 

 infold of much later date. 



Through the kindness of Mr. Fletcher and Mr. Davis, of the 

 British Museum, I have been allowed to examine the series of 

 specimens from the St. Gothard Tunnel in that collection. They 

 correspond in general with the succession above indicated, except 

 that I have failed to identify the granitoid rock of the summit 

 plateau. Leaving, however, for a moment the question of cor- 

 relation, we see that the St. ( lothard section presents us with an 

 instance of folding on a gigantic scale, and of the fan structure, 

 doubtless with many minor flexures and faults. 



In the neighbourhood of the Val Piora we get an important 

 succession. The ascent to the hotel from the Val Bedretto 

 passes in the main over a series of micaceous schists and rather 

 friable gneisses, which arc a prolongation of an axis exposed in 

 the mountains south of Airolo and fairly correspond with much 

 of the rock (excepting the granitoid) forming the upper part oi 

 the St. Gothard Pass. To this succeeds a series which, though 

 more calcareous, clearly represents the garnetiferous actinolitic 

 scries of the southern slopes, and to this a group closely resem- 

 bling the Lustrous Schists. 



( To be continued. ) 



UNIVERSITY AND EDUCATIONAL 

 INTELLIGENCE 



Cambridge. — The Electors to the Professorship of Pathology 

 will meet for the purpose of electing a Professor on May 24. 

 The stipend of the Professor is 800/. a year, exclusive of fees, 

 but he must not engage in the p.:vr..e nractice of Medicine or 

 Surgery. 



Prof. Macalister lectures to-day on the Race Types of the 

 Human Skull ; on Saturday, on the Race Variations of the Skin, 

 Hair, and Soft Parts ; and on Tuesday, the 13th, on the Ana- 

 tomical Characters of the Prehistoric and Early Historic Races 

 of Britain : on each day at 1 p.m. 



In the Long Vacation Prof. Macalister will take a Class in 

 Osteology, and the Demonstrator will have a class for Practical 

 Histology. 



The new buildings for Prof. Stuart's Museum of Mechanism 



will be ready to receive their contents this term, and il i n 



mended that the buildings to provide for the Department of 

 Botany be at once proceeded with, to be ready for use at the 

 beginning of Octi iber. 



SOCIETIES AND ACADEMIES 

 London 



Royal Society, May 1. — "On the Connection of the 

 Himalaya Snowfall with Dry Winds and Seasons of Drought in 

 India." By Henry F. Blanford, F.R.S. 



In this paper the author points out that for some years past it 

 has been suspected that the snowfall of the Himalaya has a direct 

 influence on the dry land winds of North-Western India. The 

 connection of the two was first noticed in 1876 and 1S77, the 

 first -named a year of drought and famine in Southern India, the 

 second the same in the North-Western Provinces, Rajputana, and 

 Central India. Messrs. Hill and Archibald, about the same 

 time, called attention to the circumstance that excessive winter 

 rainfall in Northern India is usually followed by defective rains 

 in the summer or monsoon season. This inference is strength- 

 ened if the rainfall of May be included in that of the winter and 

 spring instead of in that of the summer, as is shown by a table 

 for the eighteen years from 1864 to 1881 inclusive. Fourteen of 

 these years give results agreeing with Messrs. Hill and Archi- 

 bald's views, and only four differ from their conclusions : two 

 out of these four, viz. 1876 and 1880, being found on further 

 investigation distinctly to confirm the theory, whilst data are 

 wanting with regard to the other two years. 



Alter some details concerning the meteorology of the area in 

 tire years 18S1-82, the writer gives a description of the unusual 

 snowfall on the outer ranges of the Himalaya in the spring of 

 1S83, and of the extensive drought in Northern, North-Western, 

 and part of Central India that followed. In this instance a 

 warning forecast of dry weather and retarded rainfall was pub- 

 lished in the Gazette of India on June 2, and this forecast is 

 shown to have been justified by the event, the rainfall in July 

 and August over large portions of India having been much below 

 the average. 



In an account of the meteorology of the land winds it is shown 

 that from November to February they tend to circulate anti- 

 cyclonically round the axis of maximum pressure, extending from 

 the Punjab and Sind across Rajputana and Central India towards 

 ( hissa. In March a barometric minimum is established over the 

 Hyderabad plateau, and this extends to the north and north-east, 

 the wind currents becoming cyclonic around the depression. To 

 the eastward of this area some rain falls in the spring, but 

 Western India from Belgaum to the Punjab is practically rainless 

 from November till May, and is the dry wind area. It is then 

 shown that the supply of air for the dry wind is derived from an 

 upper stratum by convective interchange. After rain and snow- 

 on the Himalayas the dry winds are supplemented by an outflow 

 iil cold air from the hills accompanied by a wave of high pressure 

 tward from the valley of the Indus. 



The following summary and conclusions are given : — 



(I.) The experience of recent years affords many instances of 

 an unusually heavy and especially a late fall of snow on the 

 North-Western Himalaya being followed by a prolonged period 

 of drought on tlie plains of North-Western and Western India. 



(2.) On tabulating the average rainfall of the winter and 

 spring months at the stations of the North-Western Himalaya, 

 year by year, for the last eighteen years, and comparing it with 

 the average rainfall of the North-Western Provinces in the ensu- 

 ing summer monsoon, it is found that with four exceptions an 

 excessive winter precipitation on the hills is followed by a deficient 

 summer rainfall on the plains, and vice vers&. Of the four 

 apparent exceptions, two are found to afford a striking support 

 to the first proposition. 



(3.) The west winds which, in Western and Northern India, 

 are characteristic of seasons of drought as abnormal winds, are 

 identical in character with the normal winds of the dry season, 

 and appear to be fed by descending currents from the North- 

 Himalaya, and possibly the western mountains gene- 

 rally. 



(4.) It is a common and well-known phenomenon of the 

 wintei months that a fall of rain and snow on the North-Western 

 Himalaya is immediately followed by a wave of high pressure 

 advancing eastwards from the western mountains, accompanied 

 with dry cool north-west winds. 



(5.) The conclusion is that an unusual expanse of snow on the 

 North-Western Himalaya, whether due to the unmeltcd residue 

 of an unusually copious winter snowfall, or to an unusually late 

 fall in the spring months, acts, at high levels, in the summer 

 months, in somewhat the same way as the ordinary falls of snow 

 ami rain on the Lower Himalaya do at low levels in the winter 



