"Ah! just so," returned Nugent.  "Now _we_ are firing because, although we can't be absolutely certain in this darkness, we think that there is a body of men out there who would be not altogether disinclined to rush the camp, if we gave them the opportunity; so we are just potting at them--or what we fancy to be them--whenever we get a clear enough sight of them, just as a hint that we are awake.  But as to assistance--n-no, I don't think we need any, at least not at present.  Should we do so, later on, I will blow a blast on this whistle of mine."  And he produced from his pocket a whistle possessing a particularly shrill and piercing note, with which he had been wont to summon Cupid to the midshipmen's berth aboard the _Psyche_, when that individual's presence had been needed with especial urgency.