252 



Professors W. E. Ayrton and J. Perry on 



above equation. Choosing, for convenience, At equal to 150 

 seconds, and putting 



v ~ y 

 we find from the curve AAA : — 





t. 



T. 



Equations. 



1125 



42-53 



4-33 # + .? = 42-53 



1275 



38-5(5 



3-61y+*=38-56 



1425 



35-22 



3-08 y+x = 35-22 



1575 



32-33 



2-70y+.r=32-33 



1725 



29-86 



2-23 y+x= 29-86 



1875 



2777 



1-95^+^=27-77 



2025 



2600 



1-59^+^=2600 



2175 



24-54 



l-33?/+^ = 24-54 



2325 



23-30 



1-15^+^=23-30 



2475 



2221 



l-03y+^=22-2I 



2625 



21 22 



0-95?/+^= 2 1-22 



Adding the above equations, we get 



23 95 y + lLe= 323-54. 



Multiplying each equation by the coefficient of y in it and 

 adding, we find 



64-91 y + 23-95^ = 783-8; 



and from these two equations we find 



^=15°-87 C, 



1 = 0-1609, 



and therefore 



y 



wor X ^ =0-00107. 

 v dt 



These values of x and m were applied to every observation to 

 determine 1ST; and the values of log N so obtained are given 

 below : — 



logN. 



1-9336 



1-9324 



1-9312 



1-9278 



1-9266 



1-9233 



1-9231 



1-9244 



1-9252 



1-9226 



1-9134 



