its well merited rank along with that of Dulong and Petit as a most
valuable means of checking molecular weights, especially in
determining which of two or more possible values expresses the
truth.--_Nature._

* * * * *

[Continued from SUPPLEMENT, No. 642, page 10258.]




THE DIRECT OPTICAL PROJECTION OF ELECTRO-DYNAMIC LINES OF FORCE AND
OTHER ELECTRO-DYNAMIC PHENOMENA.[1]

[Footnote 1: An expansion of two papers read before the A.A.A.S.
at the Ann Arbor meeting.]

By Prof. J.W. MOORE.


II. LOOPS.

If the wire, with its lines of force, be bent into the form of a
vertical circle 1-1/8 in. in diameter, and fixed in a glass plate,
some of the lines of force will be seen parallel to the axis of the
circle. If the loop is horizontal, the lines become points.

[Illustration: Fig. 14.]