As for silver, I never could see any degree of fire make it part with any of its three principles. ...But admitting, that some parts of the silver we… - Robert Boyle

That then, that I wish for, as to systems, is this, that men, in the first place, would forbear to establish any theory, till they have consulted with (though not a fully competent number of experiments, such as may afford them all the phænomena to be explicated by that theory, yet) a considerable number of experiments, in proportion to the comprehensiveness of the theory to be erected on them. And, in the next place, I would have such kind of supestructures looked upon only as temporary ones; which though they may be preferred before any others, as being the least imperfect, or, if you please, the best in their kind that we yet have, yet are they not entirely to be acquiesced in, as absolutely perfect, or uncapable of improving alterations.

The phaenomena afforded by trades, are a part of the history of nature, and therefore may both challenge the naturalist's curiosity and add to his knowledge, Nor will it suffice to justify learned men in the neglect and contempt of this part of natural history, that the men, from whom it must be learned, are illiterate mechanicks... is indeed childish, and too unworthy of a philosopher, to be worthy of an honest answer.

And truly... if men could be persuaded to mind more the advancement of natural philosophy than that of their own reputations, it were not, methinks, very uneasy to make them sensible, that one of the considerablest services, that they could do mankind, were to set themselves diligently and industriously to make experiments and collect observations, without being over-forward to establish principles and axioms, believing it uneasy to erect such theories, as are capable to explicate all the phænomena of nature, before they have been able to take notice of the tenth part of those phænomena, that are to be explicated.