TO CORRESPONDENTS. 



The Editor is much obliged by the Communication signed 

 N. L., and begs to know whether the Pyrometer therein sug- 

 o-ested has undergone the test of experiment, since it is theoreti- 

 cally objectionable. 



The Letter signed Boyle has reached its destination. The 

 tube, if elastic, would be compressed by the exhaustion; if of 

 metal, the obstacle would not close it sufficiently to answer the 

 intended purpose. 



We regret our inability to answer the Queries of C. A. H. 



A New Edition of Mr. Brande's Manual of Chemistry is now 

 preparing for the press. 



