ng results, although he was
actually too small to reach the eyepiece of his leveling instrument
without the aid of a camp-stool which he carried about with him. He
brought out some of the mechanical drawings he had worked over, and had
machinery made after them, and whenever his inventions were tried they
met with success.

For several years John commanded his six hundred men at the Goeta Canal,
and then he decided to enter the army. He had grown tall, and was noted
for his great strength and skill in feats of arms. At seventeen he was
made an Ensign in the Rifle Corps, and soon after Lieutenant in the
Royal Chasseurs. He was fond of the life of the army, but he saw there
was no great future in it for him, and he could not give up his passion
for science and invention. He procured an appointment as surveyor for
the district of Jemtland, and found himself free again to work on his
own lines.

Sweden is a rugged country, its northern part serried by great fiords,
its mountains steep and often desolate, its forests thick and many. The
young surveyor was in his element roughing it through the wild country,
with an eye to improving it for cultivation and for defense, making
elaborate maps of its hills and valleys, and charts of its fiords and
bays. He had a genius for such work, and the drawings he sent back to
Stockholm were invaluable for the development of Sweden. The surveyors
were paid according to the work they did, but John Ericsson worked so
rapidly that the officials were afraid it would cause a scandal if it
were known how much money he was receiving, and so they carried him on
their account-books as two different men and paid him for two men's
work.

In his spare hours in Jemtland and Norrland John was busy with
inventions. As a boy he had been delighted to watch his father make a
vacuum in a tube by means of fire. Now he worked over uses to which he
could put that idea, and finally invented a flame engine based largely
on that principle. That success led him to study engines more deeply,
and had much to do with deciding his later career.

Sweden had shown the world much that was new in the building of the Goeta
Canal, and many of the improvements had been due to the boy cadet
Ericsson. He was now persuaded to write a book on "Canals," explaining
his inventions and describing the Swedish plans. In such a scientific
book the drawings of diagrams were as important as the writing. As soon
as John realized that,