B. Davis — Small closed Cylinders in Organ-pipes. 187 



No. 5. Capsule cylinders. 

 Amplitudes. Number of rows. 



2A 2 3 6 10 



•39 2- 2'75 2'4 1-9 



•434 1'8 2-5 2-1 1-55 



•476 2- 2-1 2-1 1-6 



•548 2* 2-5 2-2 1-66 



The most striking result obtained from the above tables is 

 that the distances between rows slightly decrease with increas- 

 ing amplitudes of vibration. The average distance between 

 the rows decreases in general as the number of rows increases, 

 excepting in the case of the smallest, No. 5 cylinders, in which 

 case the spacing increased when three and six rows were used. 

 This tendency to increase with these particular rows is also 

 exhibited by the No. 2 cylinders. The general rule may also 

 be deduced, that the larger the cylinders, the more the spacing 

 decreases with the number of rows, as will be evident by com- 

 paring the two-row and the ten-row columns in the three 

 tables. At the higher amplitudes the capsule cylinders were 

 quite violently agitated, as though the position of the loop were 

 somewhat unsteady, which increased the difficulties of accurate 

 measurement. 



The corresponding experiments were performed with paper 

 cylinders of various diameters. These cylinders were each 

 6*3 cm in length and were open at both ends, on account of the 

 circumstance that the length of one of them was nearly equal 

 to the diameter of the pipe. Since the effect to be observed 

 was a result of the forces acting at the sides and not at the 

 ends, the open ends did not affect the experiment. The open 

 ends were of advantage in that they lessened the force with 

 which the cylinders in all cases adhered to the walls of the 



The diameters of these cylinders in centimeters are given 

 below : 



No. 1 __. -5 



No. 2 .... -71 



No. 3 _ 1-00 



No. 4 1-4 



These paper cylinders were introduced into the closed cham- 

 ber of the pipe and the same experiments performed as with 

 the capsule cylinders. Each cylinder now corresponds to a 

 row as described in the previous experiments. The same 

 amplitudes of vibration were retained for the purpose of com- 

 parison. The results are given in the following tables : 



