e of the air-buffers had been
disabled, probably on account of faults in their construction, but
these could readily be replaced, and no further injury had been done
the vessel. It was not necessary, therefore, to continue the
experiment any longer, and besides, there was danger that the
Englishman, perceiving that his antagonist did not appear to be
affected by his fire, would approach closer and endeavour to ram her.
This was to be avoided, for the Scarabaeus was a much larger vessel
than Repeller No. 1, and able to run into the latter and sink her by
mere preponderance of weight.

It was therefore decided to now test the powers of the crabs. Signals
were made from Repeller No. 1 to Crab A, which had been lying with the
larger vessel between it and the enemy. These signals were made by
jets of dense black smoke, which were ejected from a small pipe on the
repeller. These slender columns of smoke preserved their cylindrical
forms for some moments, and were visible at a great distance by day or
night, being illumined in the latter case by electric light. The
length and frequency of these jets were regulated by an instrument in
the Director's room. Thus, by means of long and short puffs, with the
proper use of intervals, a message could be projected into the air as a
telegraphic instrument would mark it upon paper.

In this manner Crab A was ordered to immediately proceed to the attack
of the Scarabaeus. The almost submerged vessel steamed rapidly from
behind her consort, and made for the British man-of-war.

When the latter vessel perceived the approach of this turtle-backed
object, squirting little jets of black smoke as she replied to the
orders from the repeller, there was great amazement on board. The crab
had not been seen before, but as it came rapidly on there was no time
for curiosity or discussion, and several heavy guns were brought to
bear upon it. It was difficult to hit a rapidly moving flat object
scarcely above the surface of the water; and although several shot
struck the crab, they glanced off without in the least interfering with
its progress.

Crab A soon came so near the Scarabaeus that it was impossible to
depress the guns of the latter so as to strike her. The great vessel
was, therefore, headed toward its assailant, and under a full head of
steam dashed directly at it to run it down. But the crab could turn as
upon a pivot, and shooting to one side allowed the surging man-of-war
to