To render it either true or useful, it had to be reduced to the cautious terms employed by Kirchhoff.
Thus Foucault, in 1849, came to the verge of Kirchhoff's discovery.
Kirchhoff dated the 'later redaction' of the Odyssey between Ol.
The slow assent of physicists to Kirchhoff's dictum now becomes intelligible.
In 1859 Professor Kirchhoff made an experiment which explained those dark lines, and we will repeat it now.
It is, Kirchhoff will say, the product of the mass by the acceleration.
This definition is just as conventional as Kirchhoff's, but far less general.
It was in 1859 that Kirchhoff and Bunsen first expounded to the world the true meaning of the dark lines in the solar spectrum.
The reversal of the lines of the spectrum was seen repeatedly before Kirchhoff, and had been mechanically explained.
In the Invocation Kirchhoff cuts out the allusion to the oxen of the Sun (lines 6-9) as being inconsistent with his theory.