342 Mr. D. J. Blaikley on the Correction to be added 



Kectifying the average of the tabulated observations by the 

 value of the corrections above given, the following reduced re- 

 sults are obtained for dry air at 60° F. 



c". *b r - 9 T e ' c' 



l 2 = 19-1648 21-8852 25-7678 310483 38-8968 



E 



h = 5-9941 



6-8881 



8-1983 



9-9371 



12-5740 



^ = 13-1707 



14-9971 



17-5695 



8-7848 



8-1983 



•5865 



21-1112 



26-3228 



5. = 6-5853 

 4 



5-9941 



7-4985 

 6-8881 



10-5556 

 9-9371 



13-1614 

 12-5740 



x = -5912 



•6104 



■6185 



_^874 



•587 



R: 



2-08 



•564 



= 1-04. 



•595 



•565 



Pitch. h Feet per x 



2 second. r 



c" 507-45x2x13-1707 = 1113-91 -568 



b\>' ... 444-72x2x14-9971 = 1111-59 -587 



g' 380-81x2x17-5695 = 1115-11 -564 



e' 317-46x2x21-1112 = 1116-98 -595 



c' 253-68x2x26-3228 = 1112-91 -565 



Mean of all the obser- ^ ni4 . 10 . 576 



vations at 60° j . . 



Do. do. 32° 1083-75 



The possible sources of error in the above results would appear 

 to be chiefly these — inaccuracy in appreciation of the point 

 of maximum resonance, and error in estimating the humidity 

 of the air in the tube ; perhaps vapour rising from the water 

 surface would cause the air in the tube to be more nearly satu- 

 rated than the surrounding air. 



na 



The differences in the values of ^- are very slight, and appear 



to be due rather to errors of observation than to any variation 

 depending upon ratio of length to diameter, at least within the 

 limits of an octave. 



The second method of experiment I adopted was to sound an 

 open tube by means of a steady gentle blast across one end. 

 The tube used was the same as used for the first method; and its 

 second proper tone was sounded; so that two nodes would fall 

 within its length : the pitch was 506*8. After the pitch was 

 noted, a well-fitting sliding plug was inserted at the free end 

 and moved along the tube until the two positions were found at 

 which the note sounded agreed in pitch with that given by the 

 open tube.- The nodes thus formed were at 6*06 inches and 19*39 

 inches from the free open end, with temperature 66° F. and ten- 



