Scottish scientist and mathematician (1748–1819) known for his work on the theories of James Hutton and his proposal of an alternative to Euclid's parallel postulate. ALS, one page both sides, 4.5 x 7.25, no date. Letter to a woman. In full: “The Iceland chrystals [sic] you mention will be to me a great acquisition for I am but indifferently provided with such specimens. Beside the value they derive from association with the memory of the distinguished person to whom they belonged, they will therefore have to me a great deal of the value that comes from utility. I hope to be able to send you good accounts from the chief commissioner in the course of next week or the following. I hope you are much better, tho nothing can be more unfavorable for invalids than the weather of late.” In fine condition, with intersecting folds, a few creases and dings to the edges, and some light erased pencil notations to the top. The crystal he refers to, also known as Iceland spar, is a transparent variety of calcite used to demonstrate the polarization of light. This letter demonstrates Playfair’s interest in a range of disciplines—from theoretical mathematics to experimental physics. RRAuction COA.
