•».» 



EXPERIMENTS IN AERODYNAMICS. 



< !ollecting the values of / from the several day-' observations and reducing 

 them to a common mean temperature of 10° C and pressure of 735 mm., we 

 have the following summary of results : 



Augusl 27, 1888 0.00810 



28, " 0.00794 



October I. " 0.00757 



The observations of October I being of inferior accuracy to the others on 

 account of the wind, which ble'fl in sudden gusts, the mean of the first two days' 

 experiments, viz., # m = 0.0080, may be considered as the final value for the 

 coefficienl of normal pressure resulting from the experiments with this instrument. 



The columns headed P a0 = 0.0077 V 2 in the experiments of Augusl 27 and 

 28, and P 00 = 0.0076 I'- in the experiments of October 4, give for each obser- 

 vation of the inclined plane the computed pressure which the plane would 

 sustain if moving normally with its velocity I'. The coefficienl adopted for the 

 computation is the mean value of k . resulting from the experiments of the day. 

 The last column of the tables contains the ratio of the actual pressure on the 

 inclined plane to the computed pressure on the normal plane given in the 

 preceding column. 



These ratios from the several days' experiments are collected in the following 

 summary, and mean values are taken for the different angles of experiment. 

 These mean ratios are plotted in Fig. L,and a smooth curve is drawn to represenl 

 them. 



Table V. Summary of ratios of pressurt on inclined plane to pressure on normal plane. 



