Miscellaneous. 191 



Cliffs ; while, in the opposite direction, after overlapping the Middle 

 Drift, it reaches to the crests of the Downs over Eoyston and 

 Baldock — heights, I imagine, exceeding those he gives for it in his 

 paper. Seaeles V. Wood, Jun. 



Bbentwood, Essex. 



IMIIS C:BXjXj.A.35r:E]OTJS. 



Lectures on Mining. — In a previous number of the Magazine, 

 attention was directed to the course of lectures on practical mining 

 being given by Professor Smyth, and reported in the Mining 

 Journal; the following are the heads of the subjects treated of, 

 in continuation of those previously alluded to, viz. : — On the driving 

 of levels, and the direction which ought to be taken in seeking 

 deposits which have been lost ; on securing the ground by timber- 

 ing, and the relative value of the different kinds of wood that are 

 used in England and other countries, the nature of the ground to be 

 timbered, and the necessary precautions to be adopted ; on the em- 

 ployment of stone and other materials in walling ; on the sinking, 

 position, form, and size of shafts, in relation to the nature of the 

 strata to be passed through, and the modes of securing and protect- 

 ing their sides ; on tubbing, and the methods used for sinking through 

 difficult ground, in which the ingenious suggestion of M. Triger is 

 fully described. Following the nature of exploratory and other works, 

 called dead work, Professor Smyth treated of the difference in work- 

 ing metalliferous and stratified deposits, and on some deposits which 

 were worked by methods common to both. These lectures suc- 

 cessively appear in the Mining Journal, and are carefully and some- 

 what fully reported, and will be found useful records to the students 

 who attend the lectures, and instructive to those who have not had 

 the opportunity of hearing them. — J. M. 



The Ehtncuoceti of the Crag. — The group of Cetaceans called 

 by Eschricht Bhynchoceti, from their remarkable beak-like muzzle, 

 are represented in the present fauna by about six species, belonging 

 to four or five genera, according to Professor Huxley (Quart. Jo urn. 

 Geol. Soc. 1864, p. 395). The species described by M. Fischer, as 

 noted in our February number, probably belongs to one of these 

 genera. The fossil Bhynchoceti at present known are the Ziphius 

 cavirostris of Cuvier, of doubtful age ; Choneziphins planirostris, from 

 the Lower Antwerp Crag ; and nine sj)ecies belonging to the genus 

 Belemnoziphiiis, of which seven are known only from our English 

 Ked Crag : Choneziphius has never yet been recorded as occurring in 

 our Suffolk strata, and is known almost solely from a fine specimen 

 discovered at Antwerp, — a cast of which is in the British Museum. 

 Mr. Eay Lankester informs us that two years since he identified a laro-e 

 specimen of a Ehynchocetan skull from the Eed Crag, with the cast of 

 Choneziphius in the British Museum, and that the identification was 

 confirmed by Professor Huxley. The specimen was then in the 

 possession of Mr. John Calvert, and was almost as perfect and satis- 



