Some large burning lenses and their use by eighteenth-century French and british chemists

In scientific circles in Paris and London large burning lenses were used in the eighteenth century as a means of reaching very high temperatures. However, their great expense proved to be unjustified, for chemists found that even in good weather they did not give reproducible results. This paper is concerned only with chemical applications of the lenses, and not with theoretical discussions of the means of eliminating aberration or calculating the temperatures attained.