PROFILE OF HTEISOBAQUEOUS SHORE TERRACE 3 
of orbits be drawn and the positions of the several particles be 
connected by a curved line, that line will show the wave form 
(Figs. 1to6). The curve is a trochoid.* It may be produced 
by rolling a circle on the under side of a straight horizontal line. 
= OCC TSEC OVO TES 
COS OUI OSOIC 
t First recognized by GERSTNER, Theorie der Wellen, Prague, 1804. See p. 343 
of reprint in WEBER’sS Wellenlehre. Discussed mathematically by W. J. M. RANKINE, 
“On the Exact Form and Motion of Waves at and near the Surface of Deep Water,” 
Philosophical Transactions, 1863, page 127. 
