through the levelling-instrument; and in using it, he was obliged to
mount upon a stool, carried by his attendants for that purpose. As the
discipline in the Swedish army required that the soldier should always
uncover the head in speaking to his superior, gray-headed men came, cap
in hand, to receive their instructions from this mere child.

While thus employed in the summer months, he was constantly occupied
during the winter with his pencil and pen; and there are many
important works on the canal constructed after drawings made by
Ericsson at this early age. During his leisure hours, he measured up
and made working-drawings of every implement and piece of machinery
connected with this great enterprise; so that at the age of fifteen he
was in possession of accurate plans of the whole work, drawn by his own
hand.

His associations with military men on the canal had given him an
inclination for military life; and at the age of seventeen he entered
the Swedish army as an ensign, without the knowledge of his friend and
patron, Count Platen. This step excited the indignation of the Count,
who tried to prevail upon him to change his resolution; but finding all
his arguments useless, he terminated an angry interview by bidding
the young ensign "go to the Devil." The affectionate regard which he
entertained for the Count, and gratitude for the interest taken by him
in his education, caused the circumstances of this interview to make a
deep impression upon Ericsson, but were not sufficient to shake his
determination.

Soon after the young ensign had entered upon his regimental duties, an
affair occurred which threatened to obscure his hitherto bright
prospects. His Colonel, Baron Koskull, had been disgraced by the King,