Historic experimental evidence of Kirchhoff's radiation law

[fsonnichsen]

I am curious about the historic experimental evidence that lead to Kirchhoff's radiation law. It is easy to take for granted the ubiquitous temperature/wavelength curve that lead Planck to the quantization concept. But I wondered historically how the curve was derived.
To clarify, we routinely see this spectral distribution in the laboratory with a simple benchtop spectrometer consisting of a dispersion grating and photdiode array. One can plot the relative intensities from the latter and reveal the curve.
But how was this done in the time prior to such a device? I believe that in Kirchhoff's time the only spectral device was the "spectroscope", perhaps with a photographic plate. How were the relative intensities determined? I could not locate the key papers from that time.

thanks
Fritz

 

[trurle]

Kirchhoff did not measure spectrum, but just postulated (in 1859) the wavelength dependence being the same for all black bodies. The argument used hole-based black body and 2 heat sources (artificial one and sun).
The actual measurements of black-body spectrum would not be possible until invention of electrical bolometer in 1880.

 

[anorlunda]

How about a book recommendation? The history -- Kirchoff to Boltzmann to Plank to Dirac et all.

 

[fsonnichsen]

OK trurle. This makes sense and confirms my expectation.
I find that this whole area of physics, the precursor of quantum mechanics, is very poorly described in most of the texts I have here. It is "glossed over". How the experiment was done, whether in the lab, or from the armchair, is important as certain conditions are probably being assumed which are often not mentioned. Thus the cavity can be a conductor, leading to an electrical field boundary condition of zero at the walls etc. Obtaining the original papers is difficult for me. As anorlunda implies an appropriate book would be of value, perhaps excerpting the original papers and diverging a bit to divulge what the exact formulation of the problem is.
I never quite understood for example what the boundary conditions where, how a heated sphere is equivalent to a box with a cavity in terms of standing waves, why the waves are standing etc. And very important the necessary conclusion that the wavelengths must be quantized to avoid the ultraviolet catastrophie is poorly explained.
Thanks--Fritz

 

[vanhees71]

Well, if you find everything you've read about this history lacking detail, here's perhaps what you want ;-)):

J. Mehra, H. Rechenberg, The Historical Development of Quantum Theory, 6 vols. , Springer

It coverse however the history from 1900, not before.