"Then what's the object?" asked Ross.
"It muddles them up. They can't distinguish the Tremendous from this packet, especially in hazy weather. They've got to guess which is the substance and which is the shadow. From actual results we know now that the costly experiment has more than justified the expenditure."
The Lieutenant-Commander and his young guests continued to talk shop until it was time to go below. From that moment, conversation drifted into other channels of more or less personal interest.
Presently a loud whistle was heard from without.
"That's Jolly," declared the Lieutenant-Commander. "It's the last boat to-night, I fancy."
A few minutes later the A. P., having divested himself of his dripping oilies and sou'wester, was ushered into the cabin. Separated from his duties as Accountant Officer, he was much the same as other men. Ross could hardly believe that the jovial officer—for he did not now belie his name—was the same explosive man who had figuratively lost his head over four ounces of "tacks tinned".
Dinner over, the four officers drew their chairs close to the fire and yarned incessantly. Even the laboured rolling of the ship, the howling of the wind overhead, and the chouf chouf of the waves as they slapped against the sides, failed to remind them that they were afloat and in an exposed anchorage.
"Heard from your sister recently?" enquired Barry, addressing the A. P. He tried to ask the question in a natural tone of voice, but the midshipmen were quick to perceive a deepening of the tan in the Lieutenant-Commander's weather-beaten face.
"Had a letter only this morning," replied Jolly; "a fairly long one, too. I suppose things have quieted down a bit after the rush. My sister's a double one, you know," he added, turning to Ross and his chum.
"A what?" asked Ross.