432 XXI. ENGLAND. GREENWICH. Lat. 51 29' N. ; Long. 0'. 

 Coriections to be applied to the Means of the Hours of Observation, or Sets of Hours, 

 to obtain the true Mean Barometric Pressure for the respective Months. GLAISHER. 



English Inches. 



D 



The numbers without sign must be added 'hose with ihe sign must be subtracted. 



92 



