Oct. 7, iSSo] 



NA TURE 



53: 



The climate of the southern limit is — 

 Mean ganuary). Mean (July). 



72°'S F. S7°-S F. 



The mean of both being — • 



Mean (January). Mean Uuly). 



77°-2S F. 64°-25 F. 



Mean (Annual). 

 65°-0 F. 



Mean (Annual). 

 70°75 F- 



The present mean annual temperature of Bournemouth is 

 only S°^'4 F-> which is 20° '35 F. below its mean annual 

 temperature in the Eocene period. 



I want to know how Lyell and his followers propose to give 

 to Bournemouth, from present existing forces and causes, this 

 additional 20° F. of heat. If geologists really wish to earn the 

 respect of their fellow-workers in more exact branches of 

 knowledge, they must condescend to consider quantitative as 

 well as qualitative questions, and enter into numerical details. 

 To enable them to do so I lay down the two following 

 statements : — 



1. Of all places now existing on the same parallel of latitude 

 as Bournemouth the highest mean temperature is in 20" W. 

 long, (in the Atlantic), where the temperature is 53^'' !*"■> °'' 

 only 2°'7 F. above that of Bournemouth. 



Of all places on the same parallel the lowest mean tempera- 

 ture is found at So" W. long, (on the borders of Labrador and 

 Canada), where it is 29°'3 F., which is 2i°*l F. below that of 

 Bournemouth, and 2°'7 F. below the freezing point of water. 



Existing forces and circumstances might therefore benefit 

 Bournemouth to the extent of 2°'7 F. degrees, or might injure it 

 to the extent of 2i°'i F. ; but how is Bournemouth to gain the 

 20° of heat necessary for the flourishing of the Aramraria Cutt- 

 ninghami on its Eocene sea-shore swamps, if existing causes 

 only were at work ? 



2. The place in the northern hemisphere which is now most 

 closely allied in climate to Moreton Bay, or to Bournemouth in 

 Eocene times, is the central part of the Gulf of California, in 

 Western Sub-tropical America. 



Again, I ask geologists of the uniformitarian school to show 

 me how they propose to convert the climate of Bournemouth into 

 the present climate of tlie Gulf of California or that of Moreton 

 Bay by mere transposition of land and water, without shifting the 

 position of the earth's axis, which is an inadmissible hypothesis ? 



Trinity College, Dublin, Saml. Haughton 



September 25, iSSo 



The Naini Tal Landslip 



For the purpose of making a thorough inquiry into the details 

 of the causes that led to the above lamentable disaster an able 

 geologist would undoubtedly be required, as was suggested in 

 your leader last week. I tliink, however, that to any one who, 

 like myself, has resided even but temporarily at Naini Tal, the 

 main cause of the recent slip must be sufficiently obvious with- 

 out the aid of the geologist. 



From the account of the particular buildings overwhelmed it 

 is plain that the slip took place close to where an almost equally 

 bad one occurred some years ago (in the winter of 1865, I 

 believe), viz., just above the Victoria Hotel, on the shoulder 

 imiting the two peaks of Cheena and Lyria Kauta. 



The foot of this shoulder forms the northern border of the Tal, 

 or lake, for which the station is justly famed ; the strata com- 

 posing it, as far as I can remember, dip -^oith the slope of the hill 

 southwards towards the lake. Moreover, it faces the direction 

 from which the rain mostly comes. The conditions for the pro- 

 duction of a landslip in the direction of the lake are thus amply 

 fulfilled. 



Though landslips are not at all infrequent from this hill (one 

 occurred near Cheena when I was there, killing two natives), 

 it is from its sunny aspect and comparativtly gentle slope 

 decidedly the favourite, the station being mainly built on its 

 slopes or at its foot. 



On the hill which forms the southern border of the lake the 

 dip of the strata is in the opposite direction to the slope of the 

 hill. It is consequently much freer from landslips, and much 

 safer than the former, as only a few chips at most could be 

 detached from it on the side facing the lake, by the action of 

 rain. The nearly constant gloom however in which, from its 

 northern aspect and its steepness combined, it is necessarily 

 shrouded, as well as the lack of building area, naturally tends to 

 limit its population. This hill again on its southern- side, which 

 faces the plains, repeats the same phenomena as the shoulder 



before mentioned ; an enormous portion of it having become 

 detached towards the plains, and called pre-eminently " The 

 Landslip." 



When staying in the Victoria Hotel in May and June, 1877, 

 I always felt it would take very little to bring the whole hill, 

 and especially Government House, which appeared almost 

 vertically above us, down on top of us. The old landslip which 

 I mentioned as being close to the present hotel buried its prede- 

 cessor, and might be thought to have furnished ample warning 

 against choosing such a dangerous spot upon to which to rear a 

 fresh one. 



To guard against such disasters in future I would suggest that 

 all houses in the hill-stations should, if possible, be built mainly 

 where the strata dip in the opposite direction to the slope of the 

 hill, and that where the strata dip in the same direction as the 

 slope of the hill all proximity to steep slopes should be avoided, 

 and only the gentler slopes utilised for building on. 



I may add that the rainfall on the present occasion seems to 

 have been phenomenal, if, as the Times says, it was thirty-three 

 inches in seventy-two hours. Still, extraordinary and sudden 

 downpours of this kind must be expected, where the summer 

 rainfall has varied from forty inches in 1877 to 117 inches in 

 1862. E. Douglas Archibald 



Tunbridge Wells, October 2 



Branch-cutting Beetles 



It is rather ciurious that the story which Mr. Ober was told in 

 the Carribbees (Nature, vol. xxii. p. 216) should be generally 

 believed iu Southern Brazil also, viz., that a large beetle "seizes 

 a small branch of a tree between its enormously long nippers, 

 and buzzes round and round the branch till this is cut off." Only 

 in the Antilles this cutting of branches is attributed to a huge 

 Lamellicorn, the Dynastes hercuhs, and in Santa Catharina to a 

 large Longicorn, the Macrodontia cenncontis. 



Everybody here will tell you this story, but nobody, as far as 

 I know, has ever seen the beetle at work. Branches are often 

 cut off by some animal. On a camphor-tree in my g.arden six 

 branches, from 9*5 to I3'S centim. in circumference, have been 

 cut off; and on a Pithecolobitim for some time almost every morning 

 a fresh branch had fallen down, some being even much thicker 

 than those of the camphor-tree. The cutting is always in a plane 

 perpendicular to the axis of the branch, as it would be were it 

 made by a rotating beetle ; but in this case an annular incision of 

 equal depth all round the branch would be produced, and this I 

 have never seen. On the contrary, the incision, which causes 

 the branch to break off, consists of two parts, occupying the lower 

 and the upper face of the branch, meeting on one or on either 

 side of it, and being sep.arated by a wedge-shaped interval, which 

 is broken by the weight of the branch, and is narrower or broader 

 according to its toughness. 



Once— many years ago — I came to the Pithecolobitim tree early 

 in the morning, when a branch was just falling down, and with 

 it came down the animal by which it had been amputated. It 

 was a Longicorn beetle, the w-ell-named Oncideres ampiitator, 

 Fabr, I have since seen specimens of some other species 

 of the same genus, which had been caught by others in the act 

 of cutting branches. It is almost unnecessary to add that they 

 do so by gnawing, and not by whirling round the branches. 



Blumenau, Santa Catharina, Brazil, Fritz MUller 



August 13 



The Tay Bridge Storm 



In Nature, vol. xxi. p. 468, Mr. Ley asks, relative to my 

 letter on the Tay Bridge storm, which appeared iu Nature, 

 vol. xxi. p. 443, on what evidence I state " that when the 

 velocity of the cyclone centre is very great, the strength of the 

 wind for any gradients is increased, or at all events becomes 

 more squally and gusty." 



I much regret the circumstances which have prevented my 

 replying to him sooner, but may now state shortly the three 

 principal pieces of evidence which led me to that conclusion : — 



1 . My own observation in a large number of cyclones where 

 the velocity of translation was very great, there has been a quality 

 of gustiness or squalliness and intensity generally greater than is 

 usual for the observed gradients. 



2. Ever since the barometer was invented it has been known 

 that a rapid fall of the mercuiy indicates worse weather than a 

 slow one. Now we know that the rate at which this fall takes 

 place at any station depends;— (i) On the steepness of the 



