1863.] 517 



Let log n=log [log B log 60-00004 . (M ro)] 



4- l-8261420 + log(836 + A + a) 

 =log [log B-log 6-0-00007. (M'-w')] 



+ 2-0814145+log(500 + A'-M') 

 =log [log B-log 6-0-00009 . (M"-0i")] 



+ 2- 1 783245 -f log (400 + A" + a"), 

 then A-H= + -001 . wJ+A"-H", 



where 1-8261420 + log 900=2-0814145 +log 500 



= 2-1783245 -f log 400=4- 7803845 =log 60309*19. 



This form requires less previous preparation, avoids the logarithms 

 of numbers near to unity as f 1 -f- V and allows of the use 



of foreign data to obtain the result in English feet, so that it only 

 becomes necessary to reduce the height of the lower station to 

 English measures. 



V. " BessePs Hypsometric Tables, as corrected by Plantamour, 

 reduced to English Measures and recalculated. " By 

 ALEXANDER J. ELLIS, Esq. Communicated by Dr. NEIL 

 ABNOTT. Received February 23, 1863. 



These Tables, with the preliminary explanations respecting their 

 correction and reduction, have been, by direction of the Council, com- 

 municated to Admiral FitzRoy for insertion in the " Meteorological 

 Papers published by Authority of the Board of Trade," and will 

 appear in the twelfth Number of the series. 



