Its movements appeared to become uncertain, as though puzzled by the trace of human habitation; it turned in different directions, coiling and uncoiling, and frequently rearing its head, but keeping about the middle of the space in front of the cave, when suddenly, as though unable to resist doing so, one after another the boys fired, and even their mother discharged her gun. The shots took not the slightest effect beyond startling the monster, whose movements were accelerated. Fritz and I also fired with steadier aim, but with the same want of success, for the monster, passing on with a gliding motion, entered the reedy marsh to the left, and entirely disappeared.

A wonderful weight seemed lifted from our hearts, while all eagerly discussed the vast length and awful though magnificent appearance of the serpent. I had recognized it as the boa constrictor. It was a vast specimen, upward of thirty feet in length.

I explained to the children that its name in South America is Boaguacu; the first syllable of that word, with the Latin addition, which indicates that it kills its prey by pressure, or "constriction," gives the name by which it is commonly known.

The near neighborhood of this terrific reptile occasioned me the utmost anxiety; and I desired that no one should leave the house on any pretext whatever, without my express permission.

During three whole days we were kept in suspense and fear, not daring to stir above a few hundred steps from the door, although during all that time the enemy showed no sign of his presence.

In fact, we might have been induced to think the boa had passed across the swamp, and found his way by some cleft or chasm through the wall of cliffs beyond, had not the restless behavior of our geese and ducks given proof that he still lurked in the thicket of reeds which they were accustomed to make their nightly resting place.

They swam anxiously about, and with much clapping of wings and disturbed cackling showed their uneasiness; finally taking wing they crossed the harbor, and took up their quarters on Shark Island.

My embarrassment increased, as time passed on. I could not venture to attack with insufficient force a monstrous and formidable serpent concealed in dense thickets amidst dangerous swamps; yet it was dreadful to live in a state of blockade, cut off from all the important duties in which we were engaged, and shut up with our animals in the unnatural light of the cave, enduring constant anxiety and perturbation.

Out of this painful state we were at last delivered by none other than our good old simple-hearted donkey; not, however, by the exercise of a praiseworthy quality, such as the vigilance of the time-honored geese of the Capitol, but by sheer stupidity.

Our situation was rendered the more critical from having no great stock of provisions, or fodder for the animals; and the hay failing us on the evening of the third day, I determined to set them at liberty by sending them, under the guidance of Fritz, across the river at the ford.