The Calculation of Glass Constants on the Basis of Recent Investigations

JSGT 1928 V12 T082-T118

When one speaks of “a calculation of constants” this can signify nothing more than the interpolation of unknown magnitudes between accurately determined values by means of a more or less probable hypothesis. As a rule, this hypothesis takes the form of a curve linking the values of the constants which correspond with the varying proportions of the chemical constituents of the glass. The curves can suitably be expressed by equations. In many cases they can be considered partly as a straight line. The calculation of the constants then takes the simple form of linear relationships. There are now available very many valuable data on the physical properties of glasses; but it is a fact that in the glass industry, a few works excepted, no noteworthy use has been made of these data. This is due to the fact that the form in which the results ·are set out is difficult of understanding by the practical glass man, or in itself is unsuitable for practical application. Moreover, the type of glasses investigated and the constants determined have often been of too little interest to the glass industry.

E. Zschimmer (Translated by W. E. S. Turner)