206 On Lithographic Printing.— Account of the Roch in the 



in the higher regions of the atmosphere, where it is equally 

 spread, and where it must naturally be compelled towards 

 the poles by the perpetual current of the air from the equator 

 towards them. Such an accumulation not only might furnish 

 the reason of the fi-equency of that decidedly electrical phae- 

 nomenon which is called aurora borcalis on the North, and 

 which is not less rare towards the Southern Pole, but might 

 perhaps render a just reason for the gi-eat part which the at- 

 mos})herical water might take in the formation of the inex- 

 haustible ices of the polar regions. 



XXXVIII. On Lithographic Printing. 

 To the Editors'Of the Philosophical Magazine a7idJournal. 



Gentlemen, — xIaving found considerable inconvenience 

 arise from the use of grease on the surface of the stretched 

 leather in the tympan irame, over which the scraper passes, 

 —on account of the dirt it creates, the injury it occasions to 

 4;he leather, and the waste of paper, — I have tried various sub- 

 stitutes. 



The most successful experiment I have yet made, has been 

 widi Castile soap rubbed over the leather with a little water. 

 It very speedily produces, by the action of the scraper passing 

 over it, a glossy surface ; and I feel confident that the labour 

 in workmg the press is even less than when grease is em- 

 ployed. This, in addition to the other advantages it possesses, 

 viz. cleanliness and oeconomy, strongly recommend its use to 

 those employed in lithographic prmting — particularly those 

 who practise it as an amusement. 



I am, gentlemen, your obedient servant. 

 The Lithographic Press, Charles M. WlLLICH. 



8, Pickett-street, Strand, Sept. 23, 1822. 



XXXIX. Short Account of the Books in the Neighbourhood 

 of St. John's, Newfoundland. By Mr. iontf Baiud*. 



In approaching the fishing grounds on the coast of America, 

 the soundings were from sixty to thirty fathoms; over the 

 great Bank of Newfoundland, generally about thirty-five. The 

 lead brought up a fine sand, and frequently small pieces of a 

 rough flint, together with particles of a green smooth mineral, 

 in the form of coarse green sand. It is certainly a singular 

 fact, that so large a portion of shallow water should exist so 



* From ihc Memoirs of tlie Werncrian Natural Ilistorv Society fof 

 1821-2^ \'ol. iv. Part I. 



far 



i 



