second warning to the
world by the Spirit of Prophecy_ (London, 1760), and _Signs of the Times;
or a Voice to Babylon_ (London, 1773).

[582] His real name was Thomas Vaughan (1622-1666). He was a fellow of
Jesus College, Oxford, taking orders, but was deprived of his living on
account of drunkenness. He became a mystic philosopher and gave attention
to alchemy. His works had a large circulation, particularly on the
continent. He wrote _Magia Adamica_ (London, 1650), _Euphrates; or the
Waters of the East_ (London, 1655), and _The Chymist's key to shut, and to
open; or the True Doctrine of Corruption and Generation_ (London, 1657).

[583] Emanuel Swedenborg, or Svedberg (1688-1772) the mystic. It is not
commonly known to mathematicians that he was one of their guild, but he
wrote on both mathematics and chemistry. Among his works are the
_Regelkonst eller algebra_ (Upsala, 1718) and the _Methodus nova inveniendi
longitudines locorum, terra marique, ope lunae_ (Amsterdam, 1721, 1727, and
1766). After 1747 he devoted his attention to mystic philosophy.

[584] Pierre Simon Laplace (1749-1827), whose _Exposition du systeme du
monde_ (1796) and _Traite de mecanique celeste_ (1799) are well known.

[585] See note 117, page 76.

[586] John Dalton (1766-1844), who taught mathematics and physics at New
College, Manchester (1793-1799) and was the first to state the law of the
expansion of gases known by his name and that of Gay-Lussac. His _New
system of Chemical Philosophy_ (Vol. I, pt. i, 1808; pt. ii, 1810; vol. II,
1827) sets forth his atomic theory.

[587] Howison was a poet and philosopher. He lived in Edinburgh and was a
friend of Sir Walter Scott. This work appeared in 1822.

[588] He was a shoemaker, born about 1765 at Haddiscoe, and his
"astro-historical" lectures at Norwich attracted a good deal of attention
at one time. He traced all geologic changes to differences in the
inclination of the earth's axis to the plane of its orbit. Of the works
mentioned by De Morgan the first appeared at Norwich in 1822-1823, and
there was a second edition in 1824. The second appeared in 1824-1825. The
fourth was _Urania's Key to the Revelation; or the analyzation of the
writings of the Jews..._, and was first published at Norwich in 1823, there
being a second edition at London in 1833. His books were evidently not a
financial success, for Mackey died in an almshouse at Norwich.

[589] Godfrey Higgins (1773-1833), the archeologi