From the PHILOSOPHICAL MAGAzINB, vol. xlii. Movember 1921, 
On the Decay of Oscillation of a Solid Body in a Viscous 
Fluid. By TV. H. Havetocgn, B.S. 
ile ee decay of rotational oscillation of a cylinder 
or a sphere in a viscous liquid is a well-known 
problem in Hydrodynamics ; among more recent researches, 
reference may be made to the work of Verschaffelt +, 
Coster {, and others. In those papers it is remarked that 
+ G. E. Verschaffelt, Amsterdam Proc. xviii. p. 840 (1916); also 
Comm. Leiden, cli. (1917). 
{ D. Coster, Phil. Mag. xxxvii. p. 587 (1919). 
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