NA TURE 



[May 7, 1874 



of fact" touching the new Inch Ordnance map, Mr. Christie and 

 I are both riglit. That is, he has a copy to show for his asser- 

 tion ; I have one to show for mine. But the great question is 

 not what is the "matter of fact " as touching maps, but what is 

 the matter of fact in nature ; and I assert that Loch-na-Davie 

 has but one outlet, to the south, to Glen lorsa. My words in 

 the . -I //it-'iitvim are — " The water-parting is a few yards to the 

 north of the loch, I should o,„-ss at the spot where a heap of 

 stones stands, apparently lately tlirown up ; " and from there 

 there is a slight trickling i>i/ct to the loch. I ended my letter 

 thus — " Most gracious reader of the Athcmuini^ go take a tourist 

 ticket to Glasgow from liuston Square. Then a lovely run in a 

 Clyde steamer to Arran, and judge for yourself." May I repeat 

 this advice to the "gracious reader" of Nature, for assuredly 

 there is no arguing as to a " matter of fact." 



As a matter of opinion, I do not think ihat any quantity of 

 rain could turn the northern inlet into an outlet. That is, I 

 think that at the southern end there is room to emit any over- 

 flow before the northern end could be flooded. Mr. Christie 

 seems to suppose a constant double outlet. Dr. Bi7ce, more 

 modest, only claims this in "winter and wet summers" (3rd 

 edition, p. 5), or " when it rises about eighteen inches above its 

 level in dry weather" (p. 130). 



Alresford, May I George Greenwood 



I observe that a correspondence has been going on in the 

 columns of Nature on the subject of lakes with double out- 

 lets. It may interest your readers to learn that some glaciers 

 afford instances of the same phenomenon. One of the most 

 remarkable of these is the Glacier d'Arsine, in the old P'rench 

 province of Dauphine (now the Departement des Ilautes Alpes). 

 This glacier is broad and short ; its moraines are extraordinarily 

 large. It ends just on the watershed between the Romanche 

 and Guizanne, and consequently streams flow from it in both 

 directions. On one side, the stream forms a branch of the 

 Romanche, which fall into the Drac, the united stream entering 

 the here below Grenoble. On the other side, the stream flows 

 down to the Guizanne, which, after receiving the Clairee near 

 Brian9on, assumes the name of tlie Durance, and falls into the 

 Rhone below Avignon. This watershed is a proloujation of 

 that over which the magnificent route imperiale (magnificent in 

 point of engineering and of scenery) of the Col du Lautaret has 

 been carried. This glacier is very rarely visited, though the 

 above-mentioned phenomenon has been remarked before. Per- 

 haps some of your readers can supply the names of other 

 glaciers which present a similar phenomenon. I need only add 

 that these observations were made during personal visits to the 

 Glacier d'Arsine on July 15 and 17, 1S73. 



Exeter College, Oxford W. A. B. Coolidge 



Trees "Pierced" by other Trees 

 The natural phenomenon of one tree within another is very 

 frequently witnessed in India in the case of the "pipal" (vulg. 

 fci-ptil) and the palmyra. The first instance which drew my 

 .attention to it was one in which a very large specimen of the 

 former with a stem some 4 ft. thick was surmounted by a 

 towering palm which seemed to grow out of, and in continuation 

 of, the solid trunk at a height of about 30 ft., and rose to a 

 height of 30 to 40 ft. more. 1 speak from recollection only. An 

 amicable dispute took place between two natives, of whom I 

 inquired about it — both strangers to the locality — the one 

 declaring that the palm grew up inside the tree from the ground, 

 and the other that it grew upon it. Subsequently I saw numbers 

 of others in all stages, and recognised the fact that the fig grows 

 up by the side of the palm and gradually eneloses it, so com- 

 pletely as to defy examination of the resulting trunk. The tree 

 that I speak of was by far the most remarkable S]iecimen of the 

 kind, and therefore I give its locality. It is a little south of the 

 town of Kodangal, in the Hyderabad country, long. 77° 40' E., 

 lat. 17° 6' N. J. Herschel 



May 5 



Colonel Greenwood's solution of the beech-tree pierced 

 by a thorn plant is undoubtedly correct. The New Forest 

 affords many cases of the branches of that tree growing together 

 and (orning holes apparently through the trunk. Ivy gives the 

 most striking and familiar examples of its runners crossing and 

 uniting ; it is not unusual to find a triangular arrangement of 

 runners which cross each other at intervals of a few inches apart. 

 It may be as well to draw your readers' attention to the spas- 

 mo ic way in which the leaves of the beech burst in sprmg : 

 sometimes an entire branch, at others a single twig with less 



than twenty leaves, will be in full leaf *. week or ten days before 

 the buds have generally burst. G. H. H. 



In reference to this subject I many years ago met with an 

 instance of a birch growing out of the fork of an oak. 



The trunk of the oak at perhaps S ft. or 9 ft. from the ground 

 divided into two large arms from between which a birch sprung. 

 The oak was of very considerable age but apparently was not 

 hollow (of this, however, I am not positive). The birch was 

 perhaps 12 ft. or 14 ft. high. P. P. C. 



The Antipathy of Spiders to the Wood of the Spanish 

 Chestnut 



Can any of your readers establish the truth of the following 

 assertion? Spiders' webs are never found upon beams from the 

 Spanish or sweet chestnut tree, even when the timber is several 

 centuries old. The keeper of the ruins of Beaulieu Abbey, in 

 Hampshire, asserts that this is a fact, and the buildin;;s of the 

 Abbey, where beams of Spanish chestnut are used, are free from 

 the invasion cf spiders. His attention was drawn to this four 

 years ago, and since then his observations have not thrown any 

 doubt upon its accuracy. 



Birkenhead, April 23 G. H. H. 



FLOWERS OF THE PRIMROSE DESTROYED 

 B r BIRDS 



WE have received several additional letters on 

 this subject, the important statements in which 

 we have brought together here, in continuation of last 

 week's article (vol. ix. p. 509). 



Prof. Newton of Cambridge, in reference to Prof. 

 Thiselton Dyer's letter of last week, writes as follows : — 



Allow me to remark that the observation of Gilbert White 

 (quoted by Prof Dyer in Nature, vol. ix., p. 509) respecting the 

 bird said to "sip the liquor which stands in the nectarium" of 

 the crown-imperial, has not, so far as I know, been confirmed 

 by anyone else. Yielding to no man in my general trust in 

 White's wonderful accuracy, I think that here we ought to 

 suspend our belief, caution being perhaps the more needed, since, 

 as has been pointed out by several of his editors, it is almost 

 certain that the bird he saw was not the bird he supposed it 

 to be. 



Major E. R. Festing writes : — 



A month ago I saw a caged hen bullfinch that would treat 

 any quantity of primroses which were given to her in precisely the 

 way described by Mr. Darwin in Nature, vol. ix. p. 482. She 

 gave one snip only to each flower, not again touching the re- 

 mains of it, which fell to the floor of the cage. 



My experience in trying to keep a small garden in London 

 some years ago was, that the yellow crocus flowers were always 

 destroyed by the sparrows as soon as they come into full bloom, 

 no doubt with the same object as the finches have in destroying 

 primroses. I do not remember that the purple or white flowers 

 suffered in the same way. 



A correspondent, dating from Exeter College, Oxford, 

 writes as follows : — 



Your article on the destruction of primroses brought to my 

 mind several facts which came under my notice lately in a manse- 

 garden in the south of Scotland. Under a cherry-tree the 

 ground was thickly planted with primroses, all the flowers of 

 which were picked by the sparrows. As not only wiis this 

 cherry-tree in flower at the time, but there was also a good show 

 of flower on the various other fruit-trees in the garden, in this 

 instance, at least, the flowers of the fruit-trees seem not to have 

 exercised a superior attraction. 



Again, I myself saw that the work was done by sparrows. 



Another writer in your article asks, if any other birds besides 

 sparrows have been seen to use fresh flowers in nest-building ? 

 In this same manse-garden, some weeks ago, I watched some 

 jackdaws busily plucking and carrying to their nests in a neigh- 

 bouring chimney the leaves, flon ers, and stalks of a variegated 

 form of the common Gleclionia hideraeea. 



Mr. J. Southwell states that in his garden in the 

 suburbs of Norwich, the yellow crocuses are yearly 

 destroyed by sparrows. He says : — 



Formerly I have seen these mischievous birds pulling 



