RIDDLES OF TROUGHEND, ENGLAND.
151
known in those parts for upwards of half a century, and who was remark-
able for his knowledge of many branches of science, as well as for consid-
erable attainments in mathematics. It is not improbable that Mr. Riddle
derived from him that taste for the science which clung to his mind with
such tenacity to the end of his life. What renders this more likely is,
that about the time, before he was twenty years of age, he made an
electrical machine with his own hands, and with it showed the ordinary
phenomena produced by that instrument. At that period, it is easily im-
agined with what wonder and alarm a ring of rustics would feel the
electric impulse sent through their bodies, with a sensation unknown
"And still they gazed, and still the wonder grew,
That one small head should carry all he knew."
before.
From Otterburn Mr. Riddle moved to Whitburn, in the County of
Durham, and while there, in 1810, his name first appeared in the Ladies'
Diary, then under the editorship of Dr. Hutton, whose friend he sub-
sequently became, and who rendered him such important assistance in
advancing his success in life. It then appears that at the age of twenty-
two he had made great progress in mathematical studies. For many
years he continued to be a distinguished contributor to the Ladies' Diary,
in which his solutions were always remarkable for beauty and accuracy.
He has said that the complete mastery of Playfair's Encylopædia, which
he accomplished, produced such an effect on his mind, as to render the
acquisition of any other mathematical subject easy. After continuing
seven years at Whitburn, Mr. Riddle, through the recommendation of Dr.
Hutton, was appointed master of the Trinity House School, Newcastle-on-
Tyne, in which he remained seven years, proving by his energies and ability
of the greatest service to the nautical education of the port, which had
previously been in the lowest possible state. In 1821, while master of
the Trinity House School, Mr. Riddle made an extensive series of observa-
tions to ascertain the longtitude of that school, and to determine by actual
experiments what confidence may now be placed in the results of lunar
observations; these observations are given in a table in his remarks on
the present state of nautical astronomy, published in 1821, and dedicated
to the Master and Brethren of Trinity House, Newcastle-on-Tyne. This
essay is admirably written, and proves that he was as able to become the
historian of science as to extend her boundaries. In 1821, by the same
powerful influence of Dr. Hutton, he was appointed Master of the Upper
School, Royal Naval Asylum, Greenwich, where he remained till the period
of his retirement in 1851. Soon after his removal to London he became
a member of the Royal Astronomical Society, to which he contributed
several valuable papers. Mr. Riddle was one of the council of that learned
body, and took an active part in all its plans for the advancement of
science. In the third volume of the Transactions of the Society there is
an able paper by him, " On Finding the Rates of Time-keepers," in which
he showed how it could be done without a transit instrument. To
amateur astronomers, and to sea-faring men not having access to such an
instrument, his method was valuable. In the twelfth volume of the same
transactions appears another of his papers, "On Longitude of Madras, by
Moon-culminating Observations," which is very elaborate, and contains
valuable directions and remarks. The most valuable work which ever
came from Mr. Riddle's pen is his "Treatise on Navigation and Nautical
Astronomy";-it was an immense improvement on the empirical com-
