On the melting of Snow around Trees. 177 



xxxix. p. 95), seems now more than ever necessary, for account- 

 ing for the Bath Oahte, the Lias Clay and Limestone, and numerous 

 other thick strata, nowhere appearing on our east coast!: and 

 since that Mr. B. has at length admitted (p. 93) " the frequent 

 disappearance of a whole series of strata on one, side of a Fault," I 

 hope that in his new Edition, he will not be found supporting the 

 very improbable position he has mentioned p.84,viz.thatthe alum 

 Shale (or clunch Clay) of the Cleveland Hills, is identical with 

 the Coul shale, intervening between the yellow Limestone a?id 

 the Coals at Pallion, 2 m. VV of Sunderland Iron Bridge : the 

 thickness of which Coal shale, I cannot think but Mr. B. has 

 over-rated, by trusting to his memory; and on which account I 

 beg to express a wish, that Mr. Goodchild would favour you with 

 an accurate and particular account of his boring for Coals under 

 the yellow Limestone, to be recorded in your work. Consi- 

 dering, that at Ferry Hill Coals have long been worked, on both 

 sides of the Turnpike Road, and within sight of it, at Pits sunk 

 through the yellow Limestone Rock*, I have been surprised to 

 see Dr. Thomson (Ann. iv. 4L>) expressing his ignorance of 

 jtfiy such pit sunk through this Limestone ; and even more so, 

 at the doubts that Mr. B. seems to express of the same fact, at 

 page S4 of your last number. 



Rlarcli 1, 1815. J. FarEY, 



XXX. 0?i the Phcenoviena attending the Roots of Plants in 

 -snotvy IVeaiJier. By Mrs. Agnes Ibbetson. 



To Mr. Tilloch. 



Sir, — Xj-AVXNG seen a letter in one of your Magazines, en- 

 deavouring to account for the phaenomenon attending the roots 

 of plants in snowy weather, and being humbly of opinion that 

 the fact is mis-stated, having last winter particularly attended 

 to the appearance in question, I shall venture to suggest a few 

 observations on the subject. 



Whenever the snow lies for any time, generally it is observed 

 to melt and pass off round where a tree or shrub shades the 

 ground. Now in reality this effect has nothing to do with the 

 tree, as I shall show. At first, indeed, it occurred to me that 

 the m jtion of the root might occasion a degree of heat which 

 might melt the snow, as I know by the dissection of roots that 

 there is much more action in them than is generally supposed, 



* A c'rcuiiistimce which I have i7icntioncd in your xliid vol. p. 53; ami 

 uhicli i\lr. B. has iiohcfil ut the top of page 124, but only for coinmenling 

 on -an iaiiiiateriMl circuinstiince mentioned byjiK;. 



Vd. 45. No. 203. Marc/i 1815^ M and 



