an elementary text book of physics by R.Wallace Stewart( my hard copy) ,but the link says its was written by John Henry Poynting?
The authors published 4 books in 1900
general physics.
sound. (Iam reading it now amazing)
light.
heat.
all books are on this link
https://archive.org/details/atextbookphysic00poyngoog/page/n8/mode/2up
R.Stewart/J Poynting SOUND 1900
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