T I M 



to be applied to the time of lh moon's meridian putssage > 

 finding the tints of high. v:ater. 



Ex. Required the time of high water at London, Sept. 2, 1823, the 

 time of the moon's transit being 22A. 39w., and her | diameter 16'. 26", 

 by the Naut. Aim. 



h. m. 



Moon's transit ~ ~*~~~~~~~~.^* H *~*~~ 2 39 

 Correction from the above Table ,~~~,~~..,~, 4- 29 



High water at full and change by 1st Table ~ 



Subtract ~~~~~ 

 Time required,* 



23 8 

 2 45 



25 53 



24 49 



TIMBER measuring. 



The customary rule for the measurement of timber is erroneous ; for, 

 according to the common rule, a tree frequently contains one-fourth 

 more timber than it is estimated at. The following formulae give both 

 the customary and true content. 



Let L = the length of the tree in feet and decimals, and 6 the mean 

 girth taken in inches ; then 



- - 



4OIHI 



= cubic feet customary. 



- = cubic feet tree eontent 



310 



