ede 
Tre EqurieMENT oF A High TEMPERATURE MEASUREMENT 
LABORATORY. 
By G. A. SHOOK. 
M®#ASUREMENT OF HIGH TEMPERATURES. 
| The first attempt to measure temperatures with any accuracy seems to 
be due to the celebrated potter, Wedgewood, although he was not the first 
by any means to recognize the importance of temperature estimation and 
temperature control in kilns in order to reproduce a given effect. In the 
time of the Romans the working of iron had undoubtedly reached an ad- 
vanced stage, but their methods and knowledge of the metallurgy of iron 
were entirely empirical. In the eighth century a writer, in outlining a 
method for obtaining high temperatures, called attention to the most diffi- 
cult part of the problem, namely, that “fire is not a thing which can be 
measured.” Even within recent years the temperature of a steel kiln was 
not known within 500 degrees C. and the values given for the temperature 
of the sun ranged from 1,500 to 1,000,000 degrees C. Today, however, with 
our advanced methods of radiation pyrometry, the student of physics can 
measure the temperature of the sun, the highest known temperature, with 
as much ease and accuracy as he can determine the specific heat of a piece 
of lead. 
It has been known for several years that numerous industrial processes, 
carried out at high temperatures, require a temperature control of 20 de- 
grees C. Mr. C. E. Foster’, in speaking of the successful production of fin- 
ished castings, remarked that there are four main factors to be considered : 
1—Composition of the material melted. 
2—Atmosphere and surroundings. 
3—Temperature. 
4—Time. 
The first two of these are taken care of by the chemist, but the third 
and fourth must be controlled by the man trained in pyrometry. It requires 
but a casual glance through the trade journals to convince one that the 
1The Foundry, May, 1909. 
