e_. M. Demonville obtained an introduction to William the
Fourth, who desired the opinion of the Royal Society upon his system: the
{293} answer was very brief. The King was quite right; so was the Society:
the fault lay with those who advised His Majesty on a matter they knew
nothing about. The writings of M. Demonville in my possession are as
follows.[634] The dates--which were only on covers torn off in
binding--were about 1831-34:

_Petit cours d'astronomie_[635] followed by _Sur l'unite
mathematique._--_Principes de la physique de la creation implicitement
admis dans la notice sur le tonnerre par M. Arago._--_Question de longitude
sur mer._[636]--_Vrai systeme du monde_[637] (pp. 92). Same title, four
pages, small type. Same title, four pages, addressed to the British
Association. Same title, four pages, addressed to M. Mathieu. Same title,
four pages, on M. Bouvard's report.--_Resume de la physique de la creation;
troisieme partie du vrai systeme du monde._[638]

PARSEY'S PARADOX.

The quadrature of the circle discovered, by Arthur Parsey,[639] author
of the 'art of miniature painting.' Submitted to the consideration of
the Royal Society, on whose protection the author humbly throws
himself. London, 1832, 8vo.

Mr. Parsey was an artist, who also made himself conspicuous by a new view
of perspective. Seeing that the sides of a tower, for instance, would
appear to meet in a point if the tower were high enough, he thought that
these sides ought to slope to one another in the picture. On this {294}
theory he published a small work, of which I have not the title, with a
Grecian temple in the frontispiece, stated, if I remember rightly, to be
the first picture which had ever been drawn in true perspective. Of course
the building looked very Egyptian, with its sloping sides. The answer to
his notion is easy enough. What is called the picture is not the picture
from which the mind takes its perception; that picture is on the retina.
The _intermediate_ picture, as it may be called--the human artist's
work--is itself seen perspectively. If the tower were so high that the
sides, though parallel, appeared to meet in a point, the picture must also
be so high that the _picture-sides_, though parallel, would appear to meet
in a point. I never saw this answer given, though I have seen and heard the
remarks of artists on Mr. Parsey's work. I am inclined to think it is
commonly supposed that the artist's pict