64 Professor Buckland's Address. 



water usually rushes up: Artesian wells are now general in Essex, where 

 they are of the greatest utility in districts that have no natural springs. 

 He also gives an interesting list of localities, both of constant and inter- 

 mitting springs, some of them very powerful, that burst out from the 

 chalk. 



Dr Mitchell has also communicated an account of deleterious gases that 

 occur in wells in the chalk and strata above it near London. The most 

 abundant of these, namely, carbonic acid gas, issues very partially and 

 only from certain strata, and produces sometimes effects fatal to persons 

 employed in digging wells. Sulphuretted hydrogen is occasionally met 

 with in chalk ; and both sulphuretted hj'drogen and carburctted hydro- 

 gen occur in beds immediately above the chalk. 



Supercretaceous Formations. — In illustration of the history of the eocene 

 division of the tertiary strata, Mr Bowerbank has concluded, from his per- 

 sonal observations at White Cliff Bay in the Isle of Wight, that there are 

 no well-defined zoological distinctions between the London and plastic 

 clays, but that in the cliffs of this bay the same shells are common to 

 alternations of these clays with one another. At Alum Bay also he found 

 many London clay fossils in beds of greenish-grey sand and clay below 

 the variegated sands and clays referred by Mr Webster to the plastic 

 clay. A similar rectification was some time ago proposed by Professor 

 Sedgwick. 



We have also witnessed, during the past year, the commencement of a 

 valuable publication by Mr Bowerbank on the fossil fruits and seeds of 

 the London clay, illustrated with very numerous and accurate engrav- 

 ings by Mr James Sowerby. 



The great attention the author has long paid to the remains of fruits 

 and seeds which occur in such vast abundance in the Isle of Sheppey, 

 whence he has collected not less than 25,000 specimens, place him in a 

 position peculiarly advantageous for the object before him. In this work 

 drawings will be given of the anatomical structure of many of these fos- 

 sils, as seen under the microscope. The simple expedient Mr Bower- 

 bank has adopted of preserving these fruits in jars of water has kept him 

 in the entire possession of every specimen ever placed in his collection ; 

 whilst the thousands of similar fossils that have been deposited in other 

 collections, including that at the British Museum, nearly all have perished 

 from the decomposition of the iron-pyrites with which they are always 

 penetrated. 



Mr Lyell has commun'cated to us a paper full of elaborate detail of 

 facts, and of ingenious speculations respecting the boulder formation, or 

 drift, associated with fresh-water deposits, in the mud cliffs of Eastern 

 Norfolk. These cliffs are in some places 400 feet high, and consist of chalk, 

 crag, fresh- water deposits, drift mud and sand, stratified and unstratified ; 

 — with superficial accumulations of flint gravel. The centre of his ob- 

 servations is the town of Cromer ; he considers the boulder formation to 

 have been accumulated on land permanently submerged, and not, byono 



