Note 615 — Chapter VII

In his Considerations touching Experimental Essays, he says (Boyle's Works, vol. i. p. 197), ‘Perhaps you will wonder, Pyrophilus, that in almost every one of the following essays I should speak so doubtingly, and use so often perhaps, it seems, it is not improbable, and such other expressions as argue a diffidence of the truth of the opinions I incline to,’ &c. Indeed, this spirit is seen at every turn. Thus his Essay on Crystals, which, considering the then state of knowledge, is a remarkable production, is entitled ‘Doubts and Experiments touching the curious Figures of Salts.’ Works, vol. ii. p. 488. It is, therefore, with good reason that M. Humboldt terms him ‘the cautious and doubting Robert Boyle.’ Humboldt's Cosmos, vol. ii. p. 730.