Oct. 1 6, 1884] 



NA TURE 



585 



have recently been rent asunder by a rift 1 50 to 200 feet 

 deep, reaching from the summit of the mountain all the 

 way down to the water. Across this rift there is no way 

 of passing, and, in order to reach the south-eastern corner 

 of the slip, it is necessary to scramble up to the top of the 

 mountain, so as to get round the crevasse. It is difficult 

 to form any adequate conception of the titanic grandeur 

 of Nature at this spot. He who has once had the oppor- 

 tunity of viewing it from the precipice of the earth-slip 

 will never forget the impression. Having finished my 

 survey here, we returned to our tent the same way we had 

 come, glad of rest, exhausted with fatigue and want of 

 sleep as we were, after thirty-six hours' continuous travel. 

 On July 28 I set out on my return journey to Myvatn, 

 taking a direct course across the northern part of 6d<48a- 

 hraun to the farmstead of Graenavatn, on the southern 

 side of the lake (Myvatn). This I did with a view to re- 

 discovering the whole of the old highway, the eastern end 

 of which I had already traced. First we shaped our 

 course directly for the northern end of HerSubreiSarfjoll, 

 guided by the beacons to which I have alluded already. 

 We crossed a pass, dividing the easternmost neck of the 

 mountains from the main range, in the eastern approach 

 to which an excessively rough lava, split by innumerable 

 rifts, had to be traversed, in which we succeeded by the 

 mode of scrambling. On the verge of one of the rifts in 

 this lava we came upon a dilapidated beacon, and again 

 upon another on the western defile from the pass, from 

 where we threaded our way along the skirts of a recent 

 and very rough lava, directing our course for the central 

 neck of HerSubreiSarfjoll. Here we were intercepted by 

 two enormous rifts, 1 00 to 150 feet deep, divided by an 

 earth-slip one mile broad, and twenty miles long. With 

 the exception of Almannagja and Hrafnagj£, near Thing- 

 vellir, these are the largest rifts in Iceland. Having suc- 

 ceeded in bringing our caravan over the eastern brim 

 down alongside the spurs of an isolated " fell," we charged 

 the western brim in vain for a long time until we came 

 upon a sort of steep pass, up through which we brought 

 our ponies, and found upon the verge three dilapidated 

 beacons, which showed that we were still on the traces of 

 the old highway. From this spot beacons may be still 

 traced in a straight direction for Fremri Namur, but 

 recent rifts and lavas have destroyed the road, which, 

 though I now knew its direction, I could pursue no 

 farther. Here, namely, we thought we had overcome all 

 difficulties, but found soon to our cost that we were mis- 

 taken. Some distance to the east of Fremri Namur there 

 is a quite recent-looking lava, very long, but narrow, 

 which evidently has welled out of a lava fissure here in 

 1875, when, besides Askja, Myvatnsoraefi also were in a 

 state of volcanic activity. This lava is not connected 

 with the well-known more northerly lavas of 1875, 

 wherefore its existence has been overlooked hitherto ; 

 and when Johnstrup constructed his map of the lava of 

 Myvatnsoraefi, he was not aware of the fact that the same 

 rift which gave birth to the northern lavas of 1875 had, 

 further to the south, given existence to this, which mea- 

 sures fully one-half of the others. To the east of this 

 lava the earth is all cut up by bottomless cracks, over 

 which it was truly a breakneck business to pass. Across 

 some we had to urge our ponies to jump, others we 

 passed by means of natural bridges of loose boulders, 

 which frequently gave way. This was travelling with 

 one's life in one's hand, and to me it is the greatest wonder 

 that no harm resulted to man or beast. To attempt 

 crossing this new lava was entirely out of the question, 

 so we had to bend our way southward along its eastern 

 skirts until we might get round its southern spur. At 

 this end of the lava I observed a peculiar rift not more 

 than thirty to forty feet long and three to four inches 

 broad, on which twelve craters were situated, in every 

 way formed and shaped as large craters are generally, but 

 of such miniature dimensions, that they looked as if they 



had been intended for toys for children ; the aperture of 

 most of them was only four to five inches in diameter, 

 that of the largest two feet. These had, however, 

 squirted forth dashes of lava to the distance of sixty feet. 

 When at last we had reached the southern end of the 

 lava, a new trouble intervened in the shape of what ap- 

 peared to be an endless rift, and utterly impassable. We 

 had therefore to make up our minds to spending the night, 

 or whatever time might be required, in finding a passage 

 across this barrier ; and after five hours' weary struggle 

 we at last managed to scramble across where the main 

 crack split up into smaller ones. This was hard work 

 for our ponies, languishing with thirst and with hardly 

 anything to eat ; and perhaps only a degree less arduous 

 for us, who in the matter of food and drink were no better 

 off. Having crossed this serious barrier, we came upon a 

 much more even tract of lava, and presently, to our in- 

 tense relief, struck a pool of water under a snowdrift in a 

 dent in the lava, where, having watered our horses, we 

 treated them to the last scanty remainder of their fodder, 

 and then went on our way. In the early morning we 

 reached the valley called Heilagsdalr in Blafjoll, where 

 we were obliged to pitch our tent in order to give the ex- 

 hausted animals the benefit of the scanty pasture which 

 a few plots of grass offered. After a few hours' welcome 

 sleep we broke up hastily, a gale of wind with rain and 

 sand-drift having burst upon us in the meanwhile. Our 

 course now lay across the spurs radiating to the eastward 

 from Blafjoll, but such was the violence of the hurricane 

 that it was well nigh impossible to sit on horseback with- 

 out being blown away, and equally difficult to guard 

 against the despairing animals being blown out of our 

 hands into the howling wilderness. After some really 

 considerable trouble and hardship, we managed to 

 scramble down a precipitous gorge into the upland 

 plateau on which the Lake of Myvatn has found its bed. 

 After having more than once lost our bearings on these 

 lower lava wilds, we succeeded at last in striking the 

 homestead of Graenavatn, exhausted with our exertions, 

 and were glad of a grateful rest in good beds, after having 

 spent a fortnight in a tent, with our saddles for pillows. 

 Th. Thoroddsen 

 Reykjahh'8, near Myvatn, August 4 



STORAGE BATTERIES 



THE importance and desirability of an efficient and 

 economical storage battery have been very widely 

 recognised, but it is at the present time pretty generally 

 felt that no existing form of storage battery is perfect, and 

 that they are on the whole extravagant and wasteful to an 

 extent sufficient to more than compensate for their unde- 

 niable convenience. It is perfectly certain that their 

 employment has not become at all general, and that they 

 have failed to realise the somewhat sanguine hopes of 

 their early promoters. 



It seems worth while to examine into the causes of this 

 partial failure, and to inquire how far the evil opinion 

 held by many practical men concerning our present 

 method of storing electrical energy is justifiable. 



One of the main objections is that storage involves a 

 loss of some 50 per cent, of the whole. Now all methods 

 of storing and transmitting energy involve some loss. To 

 say that any particular method involves a loss of 50 or 

 even 90 per cent, is not to condemn it utterly. There are 

 many cases when the convenience of storage outweighs 

 the evil of waste altogether ; three principal ones may be 

 specified. 



(1) When the power of the source would be otherwise 

 so completely wasted that every fraction of it stored is 

 clear gain. This is the case of much terrestrial water 

 power. The energy of the tides or of Niagara is enor- 

 mous, and wholly wasted so far as human activity is con- 



