Errata in No. 200. 



Page 17, fifteen lines from bottom, after acid insert a. 

 — 19, four lines from top, for N 2 O 5 read NO 3 . 



PROFESSOR TYNDALL'S NEW WORK. 



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The ' Rede ' Lecture, delivered in the Senate House before the University of 

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The Cosmical Relations of the Revolution of the Lunar Apsides. Oceanic Tides. 

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