TO OUR READERS AND CORRESPONDENTS. 



The pages of this Journal are impartially open to all communication? 

 upon the subjects of Science, Scientific Literature, and the Arts ; and it 

 is requested that they may be forwarded to the Editor, at least one 

 month previous to the period of the pubHcation of eachl^umber. 



We shall be happy to receive papers from Provincial Scientific and 

 Literary Societies, and to publish them either on the part of the Society, 

 or of their respective authors. 



' Papers which are too long for insertion, as ig the case with jnany 

 which we receive, or which are deemed unfit for this publication, will be 

 hnmediately returned to the source whence we receive them, with our 

 reasons for their retvim. 



We are indebted to Mr. Merrett, of Liverpool, for the article on ** the 

 Architecture of London," and hope again to hear fi*om him. 



The communication upon the subject of Gymnastic Exercises we have 

 been obliged to abridge more than we could have wished. It is chiefly 

 extracted fi-om the works of Mr. Shaw, surgeon to the Middlesex 

 Hospital. 



The short notice from E. S., upon the subject of Captain Head's 

 " Rough Notes," was unfortunately mislaid, and not found again till too 

 late for publication. 



We cannot exactly see the advantage of the plan proposed by our 

 correspondent at Droitwich ; and, therefore, decline pubhshing his letter 

 till we are more satisfactorily informed upon the subject. 



Mr. Mac Mullen's additional observations upon the existence of 

 chlorine in black oxide of manganese, arrived too late for insertion in the 

 present Number. 



