Oct. 23, 1879] 



NATURE 



603 



en route to St. Augustine's Bay : " As we drew near to Volotaray 

 River and town, 1 noticed a fetish tamarind tree that calls for a 

 little notice. The tree itself is one of the largest in the neigh- 

 bourhood, and is a notable object when viewed at a distance. 

 The whole aspect of it strikes the stranger at once ; its bell- 

 shaped crown, and its branches reaching to the ground being 

 particularly noticeable. I found on close examination, that its 

 trunk divides into two a few feet from the ground ; the diameter 

 of its shade is 81 feet, and its branches torch the ground all 

 round the circle. Through its branches there are other trees 

 growing, seeking the sun through its dense foliage ; some of 

 these trees are quite a foot in circumference, and there are 

 creepers clinging to them. So that the tree is a miniature forest 

 in itself. The cool shade beneath its branches was most 

 welcome. About a foot from the double trunk a trench en- 

 cu-cling the tree has been cut in the sandy soil. This trench, or 

 gutter, is about six inches deep, a foot broad, and is swept most 

 scrupulously clean by some one, and the ridges on each side are 

 patted down so that the sand may not fall into the gutter. 



" On the raised earth between the gutter and the trunk of the 

 tree are laid small baskets, mat?, fan-palm leaves, locks of hair, 

 &c., &c., and on the surrounding branches similar articles are 

 hung, evidently placed there in making a vow, or as a thank- 

 offering for some benefit, but what I could not tell. The tree 

 is some hundred yards from the town, and when we arrived and 

 inquired about it, no one knew (?) anytliing of there being such a 

 tree. . . . 



"The tamarind trees are apparently held in reverence by the 

 Tanosy as well as by the Bara, and at seme little distance from 

 Kabodo's compound, at Kiliarivo, there is a very fine specimen 

 of a fetish tree, to which they gave the name of Zdnahary. It 

 is surrounded by a very high fence of prickly pear, and the 

 narrow passage to it had been made impassable by cutting from 

 the fence portions of the thorns and strewing them across the 

 path." 



Following is the translation by Mr. Jas. Sibree, jun., L.M.S., 

 from an account by a Ilova officer, w ho cc mmanded an expedi- 

 tion against the Sakalivas in 1873: — "Before coming to this 

 village wS saw other things of a similar kind, for there is a 

 certain tree they call 'Bot6na,'\ and in this tree there is some 

 part considered as specially belonging to God. So they put on 

 it a small mat about a hand-breadth in width, and they take long 

 dry grass and twist it together, and hanging an ox-skull to the 

 tree, they colour the tree with lines of charcoal and white .clay 

 and some yellow substance resembling turmeric, and then pray 

 and render adoration before it. And many are the charms they 

 place on the tree, fastening them to it, and every charm has a 

 name peculiar to it. These are some of them : one is called 

 ' Road-stopper,' another ' Raising up at a distance,' and another 

 'Goc.'s banner.' ... In another direction which we took we 

 saw some villages with a great many trees growing round them, 

 and the largest tree which grew near the gate had a figure of a 

 woman fixed to it, and ornamented with charms. We asked the 

 meaning of this, and were told. This is the tree of adulterous 

 desires, for here those pray who want women or are about to 

 marry." 



1 may add that Mr. Richardson, mentioned above, with his 

 wife and family, have lately landed in England, per steamer 

 Agra, ixaai Madagascar. It is greatly to be hoped that the 

 reverend missionary will give a detailed account of his adven- 

 turous journey to the south-west coast. S. P. O. 



The Theory of Hailstorms 



WoUlD you kindly allow me the sp.-ice in the columns of your 

 valuable journal to make a few remarks on this subject ? Before 

 proceeding, I would like to mention three results of observations 

 on hailstorms in general. It has been observed (i) that they 

 move over the country in sharply-defined bands ; (2) that these 

 long bands have their origin or source in mountainous regions ; 

 and (3) that the air, previous to the occurrence of the storm Is 

 frequently hot and sultry, and that when it has passed, the wind 

 feels sharp and cold. 



Theorists admit that the general ion of hail seems always to 

 depend on some very sudden introduction of an extremely cold 

 current of air into the bosom of a quiescent, nearly saturated 

 mass. Now, bearing in mind the above-mentioned facts, docs it 

 not seem probable, or at least possible, that hailstorms may be 



' Bot(^na, cr Bont^na Is ;the Eaobab, or monkcy-brend tree (Afftxttstntia 



caused by a current of wind which has been forced over snow- 

 covered mountains, and thus rendered extremely cold, descend- 

 ing into the warm plains beneath, and forcing the hot and 

 saturated air resting thereon, into the higher regions of the 

 atmosphere, where the moisture would become congealed into a 

 cloud of ice particles, the condition required for the beautiful 

 theory of the formation of hailstones of Prof. Osborne Reynolds? 

 This would account for the great frequency of hailstorms in 

 Southern France, which country is subject to the influence of 

 both the Alps and the Pyrenees. The above conditions, viz., 

 snow-covered mountains and warm plains, could only occur in 

 this country in winter and spring, and it is found that the greatest 

 proportion of our hailstorms are experieaced in these seasons. 



I do not here enter into details. Should the theory be consi- 

 dered admissible, I hope on' some future occasion to give the 

 results of a full investigation of the subject, with my arguments 

 in support of the foregoing opinion. J, A. B. Oliver 



Springburn, near Glasgow, September 29 



Underground Tides 



Mention is made'in Nature, vol. xx. p. 401, of a spring in 

 the Dux coal mines, Bohemia, exhibiting ebb and flow similar to 

 tides. May not this be due to a subterranean syphon, acting pre- 

 cisely as a Field's flushing tank would in a house drainage system 

 Mention of such springs is made in Silliman's "Principles of 

 Physics." We have in cur neighbourhood not far from the 

 Mammoth Cave a surface pool about 50 feet in diameter exhibit- 

 ing this apparent tidal action. The pool is situated in the 

 cavernous limestone country that forms such a large portion of 

 cur state, and is only a few hundred yards from Green River, 

 whose peculiarly tinted waters it closely resembles. There is 

 but little doubt that the river furnishes it with water until a level 

 is reached, bringing one of the numerous underground conduits 

 in the limestone into action, when the pool ebbs. 



Louisville, Ky., U.S.A., October 9 Morris B. Belknap 



The Uses of Tails 



A VERY important function of the tail of the yak, cat, squirrel, 

 and many other anitcals, to which I drew attention some years 

 ago, has escaped the notice of Prof. Mivart. It is that the bushy 

 tails of these animals serve a very important function in pre- 

 serving their body-heat during their nightly and their wintry 

 sleep. In cold weather animals with bushy tails will be found 

 lying curled up with their tails laid carefully over their feet like 

 a rug, and with their noses buried in the fur of the tail, which is 

 thus used exactly in the same way and for the same piurpose as 

 we use respirators. 



I have a Manx tailless cat, who cannot, of course, carry on 

 this function, but he makes a very good substitute for it by using 

 the back of one of my other cats. When he cannot be so 

 accommodated, he sleeps with his hands crossed over his face, 

 "just like a Christian," as my cook says. Lawson Tait 



OC/Ji ASTRONOMICAL COLUMN 

 Binary Stars. — Dr. Doberck, of Col. Cooper's Obser- 

 vatory, Markree Castle, Sligo, continues his interesting 

 investigations on the orbits of the revolving double stars, 

 and now gives a first approximation to the elements of 

 0.2. 298, which, since the first measures by Miidler i». 

 1843, has advanced upwards of 135°, the distance, mean- 

 while, diminishing from about i^" to o''"3 ; the passage c. 

 the periastre is fixed to 188176, and the period of 

 revolution assigned is 68 8 years. It may soon be possible 

 to infer approximately the elements of several other 

 binaries as f» Herculis, O.2. 518, the duplicity of which 

 was detected by Herschel in 1783, and which has special 

 claims to the attention of the observer, from its evident 

 physical connection with the rapidly-moving star 40 

 Eridani (one, by the way, that Mr. Gill intends to attack 

 for parallax), and No. 298 of M. Otto Struve's catalogue. 

 In a new orbit of 2 3062, by Dr. Doberck, the period is 

 1 02 '94 years; periastre i835"S. 



The Satellites of Mars. — Mr. Marth has published 

 data for facilitating the calculation of the positions of 

 Deimes and Phobos (Ast. Nach., No. 2280), including for 



