On Monday, August 10, 2015 at 1:06:24 PM UTC+1, Alastair wrote:
It is a while since I had read the Pictet paper, so I assumed that it began with a description of the experiment. In fact that description is buried in the penultimate section, so it is no surprise that no-one is aware of it. Here is the appropriate section:

==============

Pictet happened to discuss his experiments with Louis Bertrand," professor of mathematics at Pictet's own Academy of Geneva. Bertrand asked Pictet whether he be-lieved that cold also could be reflected. Pictet's response, as he recorded it himself, was immediate and negative:

"He asked me if I believed cold susceptible of being reflected? I confidently replied no; that cold was only privation of heat, and that a negative could not be reflected. He requested me, however, to try the experiment, and he assisted me in it."

The apparatus was arranged as shown in Fig. 1. [See Paper] Two mirrors of tin were placed 101 ft apart. At the focus of one was a thermometer of air, which was observed with the necessary precautions, and at the focus of the other a flask full of snow.

At the instant the flask was placed for experiment, the thermometer at the opposite focus descended several degrees, and remounted as soon as the flask was removed. Having replaced the flask at the focus, and thus made the thermometer descend to a certain degree, where it remained stationary, I poured some nitrous [i.e., nitric] acid upon the snow, and the cold thus produced caused the thermometer to descend instantly 5 or 6 deg. lower.

The fact was notorious, and amazed me at first; a moment's reflection, however, explained it. This phenomenon offered nothing more than a final proof, if it had been necessary, of the reflection of heat...

================

So Pictet has demonstrated that cold radiation does exist. I rest my case :-)

Cheers, Alastair.

Unbelievable. Another ridiculous thread, around an experiment which has been fully discussed and explained on other threads, but Alastair **again** has not understood and it seems, hasn't even read the links provided to him.

Alastair clearly bases his whole belief in this ridiculous idea of cold radiation on an experiment conducted over 200 years ago, which could not be easily explained at the time, with 18th century physics, but most certainly has been since - without invoking 'cold radiation'.