Heads of lectures on a course of experimental philosophy, particularly including chemistry, delivered at the new college in Hackney / by Joseph Priestley.

  • Priestley, Joseph, 1733-1804.
Date:
Printed for Wm. Jones, no. 86, Dame-Street, and J. Rice, no. 2, College-Green,
Catalogue details

Licence: Public Domain Mark

Credit: Heads of lectures on a course of experimental philosophy, particularly including chemistry, delivered at the new college in Hackney / by Joseph Priestley. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    All arts and manufadures are derived from fcience. Thus the dodrine of me^ chanics is an application of the law of gravitation. Every thing we are capa- ble of doing by means of the fleam-en- gine is derived from our knowledge of the properties of water in fleam j and ajl the great efFeds of gunpowder we owe to our knowledge of the compofi- tion, and chemical properties, of that fubflance. Every new appearance in nature is- preceded by ibme new circumilancej, and to thisj or rather to fomething al-= ways attending it, we fay that the ap- pearance is owing. This circumflance we therefore call the caufe^ and the new appearance the effe5f of that caufe. Thus we fay that the union of phlogif- tpn to a particular kind of earth is the caufe of its becoming a metal. It is one of the principal rules of phi- lofophizing to admit no more caufes than are necelTary to account for the efFe6ls. Thus, if the ppv/er of gravity, by which B 2 heavy