Lectures on chemistry; including its applications in the arts; and the analysis of organic and inorganic compounds / [Henry Minchin Noad].

  • Henry Minchin Noad
Date:
1843
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Licence: Public Domain Mark

Credit: Lectures on chemistry; including its applications in the arts; and the analysis of organic and inorganic compounds / [Henry Minchin Noad]. Source: Wellcome Collection.

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    Stahlian theory maintained an unimpeached dominion, till upset by the ingenuity and genius of the unfortunate Lavoisier. The great talents of Mayow were not appreciated nearly as much as they deserved in his own time, nor was it till after the fall of the Phlogistic Theory that his penetration and acute- ness were fully perceived. He was the first writer who offered views worth recording upon the subject of respiration, and his speculations concerning the causes and effects of chemical affinity were quoted and enlarged upon by Newton, in the Queries annexed to the third book of Optics. They are indeed at once clever and correct, and afford a striking contrast to the rude and groundless notions that were previ- ously entertained on the subject. Mayow was the first to show that no annihilation of the particles of a compound takes place on their union, as was universally supposed. “ When,” says he, “ spirit of salt is mixed with sal volatile, sal ammontac is produced, in which it is true neither the properties of acid or alkali are apparent; yet if salt of tartar be distilled with sal ammoniac, the volatile alkali will be displaced, with all its previous characters, because, there is greater attraction between spirit of salt and tartar, than between spirit of salt and volatile alkali.” Again, to show that the acid is not destroyed in saline combinations, he instances the decomposition of nitre by oil of vitriol, which, he says, displaces the nitric acid, and the residuum in the retort furnishes vitriolated tartar. It may be asked, why, when nitre is heated, the nitric acid does not rise, for it is as we have just seen, very volatile: the reason is, that it is restrained and kept down by its attraction for the tartar, and can only be dispelled by bodies which have a stronger attraction for tartar than it. All this is strictly true, and will serve as a specimen of the penetration of the author. Newton, in following up the views of Mayow, observes, “how these attractions are performed, I do not here consider ; what
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