426 Correspondence. 



terraces look very much like old beach lines, but as they have not 

 been cut into I cannot say for certain. 



A reference to the Ordnance Map, No. 82, south-west, will explain 

 the relative position of the localities above referred to. 



I am, yours truly, 



J. M. Mello. 

 St. Thomas's Parsonage, Brampton, Chesterfield, 

 Juhj 22nd, 1867. 



DE. T. STERRT HUNT'S THEORY OF THE EAETH. 

 To the Editor of the Geological Magazine. 

 SiE, — I have read with considerable interest the very ingenious 

 theory of the ''Chemistry of the Primeval Earth," by Dr. Hunt, 

 which is contained in your issue for August, and beg your permission 

 very briefly to ask the Doctor how his theory is compatible with the 

 following facts respecting the mean densities of the sun and larger 

 planets, or whether the theory of their extensive hoUowness does not 

 more satisfactorily account for their low mean densities than does 

 that of the sun, the earth, and, by inference, all the planets increasing 

 in density to their centres. 



The following are approximately the mean densities of the sun and 

 the larger planets : — 



Sun 1-42 tJrauus I'O 



Jupiter 1-37 Neptune 0.5 



Saturn 0*5 



and those of the smaller planets are — 



Mercury 6.6 Earth 5.5 



Venus 5.6 Mars 5.6 



The densities of the asteroids are unknown, but should they be 

 ascertained, I venture to predict that they will probably be found of 

 higher mean density than are any of the planets just enumerated. 

 All the large planets have very low mean densities ; all the smaller 

 planets have high and nearly miiform mean densities. 



How are these facts to be accounted for on Dr. Hunt's theory of 

 condensation and increase of density to the centres ? 



I am, yours obediently, 

 Newcastle-on-Ttne, T. P, Barkas. 



August 6th, 1867. 



ON THE SEQUENCE OF THE DRIFTS IN THE EASTERN COUNTIES- 

 To the Editor of the Geological Magazine. 



Dear Sir, — With reference to Mr. Wood's suggestion, that I 

 should give complete sections from his "upper drift" to the beds 

 exposed on the coast, I wish to say that I have not materials by me 

 to work out the details he asks for, and it appears to me that the 

 point at issue would not be explained by exact particulars of surface 

 contour, and the position of the crags in relation to the overlying 

 drifts. There is no difference of opinion as to this, and all are 

 agreed that the gravels underlying the Boulder-clay of High Suffolk 

 correspond in height with much of the gravel superimposed on the 



