on the Resistance of the Atmospha-e to an oscillating Sphere. 327 



w = R -^ + P — —• 



^ . ,. . P^ Q 



For simplicity, put — . . = p, , _ „ = a : then 



V = ^^—P^ + i^ 



From these, 

 d.logp jdu^,/ xz d'R dp dq\ ^ 



—d§^ = -^di-'^\~T^-Ti^ydt ""Tt)- ^ 



'^•logP- 7 ^^ _ z. /'_ il ^R x^+y d^\ _„ 

 ~rf^ - ~''rf^ "'^ V r^ • rf^ z 'dtJ -^ 



dAogp _ du _dj) ^dw_ _dR _z o tj _£, 



dl ~ ~ dx dy dz~ dr ' r r^ 



x'i + n^ + 2z^ dp dp da dq x^-^y^ dp _, 

 ^^ z^ dx ^ dy -^ dx dy z dz 



^, dX , dY 

 Now -^ — must = -r-, or 

 dy dx 



^~^djdi y dxdt^ dt '^^ dydt^^dxdt' 



K y dY ^ dZ 

 And -r- must = -j— , or 

 dz dy 



" ~ r'' dt z 'dt ^ ^ dzdt dzdt 



« * J j/ d t 



And -7- must = -1—, or 

 dt dz 



