Mankind and Political Arithmetic | Page 2

his place at Oxford among the energetic men of
science who had been inspired by the teaching of Francis Bacon to seek
knowledge by direct experiment, and to value knowledge above all
things for its power of advancing the welfare of man. The headquarters

of these workers were at Oxford, and in London at Gresham College.
In 1650 Petty was made Professor of Anatomy at Oxford, and it is a
characteristic illustration of his great activity of mind that he was at the
same time Professor of Music at Gresham College. Music had then a
high place in the Seven Sciences, as that use of regulated numbers
which expressed the harmonies of the created world. The Seven
Sciences were divided into three of the Trivium, and four of the
Quadrivium. The three of the Trivium concerned the use of speech;
they were Grammar, Rhetoric, and Logic. The four of the Quadrivium
concerned number and measure; they were Arithmetic, Geometry,
Music; and Astronomy, which led up straight to God. Advance to
Music might be represented in the student's mind by his reaching to a
sense of the harmonious relation of all his studies, which, so to speak,
lived in his mind as a single well-proportioned thought.
In 1652 Dr. Petty was sent to Ireland as physician to the army of the
Commonwealth. While there his active mind observed that the Survey
on which the Government had based its distribution of fortified lands to
the soldiers had been "most inefficiently and absurdly managed." He
obtained the commission to make a fresh Survey, which he completed
accurately in thirteen months, and by which he obtained in payments
from the Government and from other persons interested ten thousand
pounds. By investing this in the purchase of soldiers' claims, he secured
for himself an Irish estate of fifty thousand acres in the county of Kerry,
opened upon it mines and quarries, developed trade in timber, and set
up a fishery. John Evelyn said of him "that he had never known such
another genius, and that if Evelyn were a prince he would make Petty
his second councillor at least." Henry Cromwell as Lord Deputy in
Ireland made Petty his secretary.
Petty's Maps were printed in 1685, two years before his death, as
"Hiberniae Delineatio quoad hactenus licuit perfectissima;" a collection
of thirty-six maps, with a portrait of Sir William Petty, a work
answering to its description as the most perfect delineation of Ireland
that had up to that time been obtained. There is a coloured copy of
Petty's maps in the British Museum, and also an uncoloured copy, with
the first five maps varying from those in the coloured copy, and giving
a General Map of Ireland, followed by Maps of Leinster, Munster,
Ulster, and Connaught. There was afterwards published in duodecimo,

without date, "A Geographical Description of ye Kingdom of Ireland,
collected from ye actual Survey made by Sir William Petty, corrected
and amended, engraven and published by Fra. Lamb." This volume
gives as its contents, "one general mapp, four provincial mapps, and
thirty-two county mapps; to which is added a mapp of Great Brittaine
and Ireland, together with an Index of the whole."
At the Restoration William Petty accepted the inevitable change, and
continued his service to the country. He was knighted by Charles the
Second, and appointed in 1661 Inspector-General of Ireland. He
entered Parliament. He was one of the first founders of the Royal
Society, established at the beginning of the reign of Charles the Second;
and the outcome of these scientific studies along the line marked out by
Francis Bacon, which had been actively pursued in Oxford and at
Gresham College. In 1663 he applied his ingenuity to the invention of a
swift double-bottomed ship, that made one or two passages between
England and Ireland, but was then lost in a storm.
In 1670 Sir William Petty established on his lands at Kerry the English
settlement at the head of the bay of Kenmare. The building of forty-two
houses for the English settlers first laid the foundations of the present
town of Kenmare. "The population," writes Lord Macaulay, "amounted
to a hundred and eighty. The land round the town was well cultivated.
The cattle were numerous. Two small barks were employed in fishing
and trading along the coast. The supply of herrings, pilchards, mackerel,
and salmon, was plentiful, and would have been still more plentiful had
not the beach been, in the finest part of the year, covered by multitudes
of seals, which preyed on the fish of the bay. Yet the seal was not an
unwelcome visitor: his fur was valuable; and his oil supplied light
through the long nights of winter. An attempt was made with great
success to set up ironworks. It was not yet the practice to employ