Miscellaneous Items. 147 
modifications of one great universal principle. This discovery is, that 
a beam of polarized light is deflected by the electric current, so that it 
may be made to rotate between the poles of a magnet; and, as we 
understand, the converse of this, that electro-magnetic rotations may 
be produced by the agency of light. ‘Thus the problem which has 
disturbed science for a long period as to the power of magnetizing iron 
by the sun’s rays, as stated by Mrs. Somervinte, Morricuint and oth- 
ers, receives satisfactory elucidation from the indefatigable industry of 
Mr. Farapay. Already has he proved the identity of machine, chemi- 
cal, magnetic and animal electricity ; and now, advancing a step higher 
in the inquiry, he finds the most ethereal principle with which we are 
acquainted capable of producing phenomena which have hitherto been 
regarded as the exclusive property of ponderable bodies only. Light, 
the subtile agent of vision, the source of all the beauty of color, is now 
shown to have some close relation with electricity, to which has long 
been referred many of the vital functions. As life and organization 
exist only where there is light, this discovery of Mr. Farapay’s would 
appear to advance us towards some knowledge of those physiological 
phenomena which are the most recondite subjects of science. 
72. Note on Prof. Twining’s Article——We have, on account of its 
ingenuity and plausibility, inserted (at P- 89) Prof. Twinine’s solution 
of the much vexed problem concerning parallel lines. We ought, 
however, to state that a scientific friend to whom we referred the paper, 
does not consider the course of reasoning satisfactory, and we have 
thought best to insert here the remarks which he has furnished.—£ds. 
The reasoning in question is certainly of a novel and ingenious char- 
acter, but is not free from steps that are objectionable. That there 
must be some fallacy in it, might be shown by pointing out cases where 
false conclusions would result from applying it with proper modifica- 
tions, though without essential change. © It will, however, be more sat- 
isfactory to learn, if possible, in what particulars the reasoning is faulty. 
On page 95, the angle BAD is determined by the condition that it be 
such as to contain all the lines which can be drawn through A, to meet 
FG or FG produced beyond G. Then it is said that CAD cannot be 
so conditioned as simply to contain all the lines that will not meet F@ 
produced as before; for in that case AD must meet and not meet FG 
at the same time. Now this conclusion appears inadmissible. It is 
founded plainly on the assumption that in determining the angle BAD - 
to be such as to contain all of a certain class of lines, every other line 
is excluded from it; in other words, that the line AD, which is the limit 
of a certain class of lines, must itself be comprehended in that class. 
This surely would not be an authorized. paste ie even if it were not 
erroneous. es 
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