Different interpretations of the word TachmÂs—Probability that it signifies the Nightjar—Various names of the bird—Its remarkable jarring cry, and wheeling flight—Mode of feeding—Boldness of the bird—Deceptive appearance of its size.

We next come to the vexed question of the word TachmÂs which is rendered in the Authorized Version as Night-hawk.

This word only occurs among the list of prohibited birds (see Lev. xi. 16, and Deut. xiv. 15), and has caused great controversies among commentators. The balance of probability seems to lie between two interpretations,—namely, that which considers the word tachmÂs to signify the Night-hawk, and that which translates it as Owl. For both of these interpretations much is to be said, and it cannot be denied that of the two the latter is perhaps the preferable. If so, the White or Barn Owl is probably the particular species to which reference is made.

Still, many commentators think that the Night-hawk or Nightjar is the bird which is signified by the word tachmÂs; and, as we have already treated of the owls, we will accept the rendering of the Authorized Version. Moreover, the Jewish Bible follows the same translation, and renders tachmÂs as Night-hawk, but affixes the mark of doubt.

It is not unlikely that the Jews may have reckoned this bird among the owls, just as is the case with the uneducated among ourselves, who popularly speak of the Nightjar as the Fern Owl, Churn Owl, or Jar Owl, the two last names being given to it on account of its peculiar cry. There are few birds, indeed, which have received a greater variety of popular names, for, besides the Goatsucker and the five which have already been mentioned, there are the Wheel-bird and Dor-hawk, the former of these names having been given to the bird on account of its wheeling round the trees while seeking for prey, and the latter on account of the dor-beetles on which it largely feeds.

This curious variety of names is probably due to the very conspicuous character of the Nightjar, its strange, jarring, weird-like cry forcing itself on the ear of the least attentive, as it breaks the silence of night. It hardly seems like the cry of a bird, but rather resembles the sound of a pallet falling on the cogs of a rapidly-working wheel. It begins in the dusk of evening, the long, jarring note being rolled out almost interminably, until the hearer wonders how the bird can have breath enough for such a prolonged sound. The hearer may hold his breath as long as he can, take a full inspiration, hold his breath afresh, and repeat this process over and over again, and yet the Nightjar continues to trill out its rapid notes without a moment's cessation for breath, the sound now rising shrill and clear, and now sinking as if the bird were far off, but never ceasing for an instant.

This remarkable cry has caused the uneducated rustics to look upon the bird with superstitious dread, every one knowing its cry full well, though to many the bird is unknown except by its voice. It is probable that, in the days when Moses wrote the Law, so conspicuous a bird was well known to the Jews, and we may therefore conjecture that it was one of those birds which he would specially mention by name.

The general habits of the Nightjar are quite as remarkable as its note. It feeds on the wing, chasing and capturing the various moths, beetles, and other insects that fly abroad by night. It may be seen wheeling round the branches of some tree, the oak being a special favourite, sometimes circling round it, and sometimes rising high in the air, and the next moment skimming along the ground. Suddenly it will disappear, and next moment its long trilling cry is heard from among the branches of the tree round which it has been flying. To see it while singing is almost impossible, for it has a habit of sitting longitudinally on the branch, and not across it, like most birds, so that the outline of its body cannot be distinguished from that of the bough of which it is seated. As suddenly as it began, the sound ceases, and simultaneously the bird may be seen wheeling again through the air with its noiseless flight.

Being a very bold bird, and not much afraid of man, it allows a careful observer to watch its movements clearly. I have often stood close to the tree round which several Nightjars were circling, and seen them chase their prey to the ground within a yard or two of the spot on which I was standing. The flight of the Nightjar is singularly graceful. Swift as the swallow itself, it presents a command of wing that is really wonderful, gliding through the air with consummate ease, wheeling and doubling in pursuit of some active moth, whose white wings glitter against the dark background, while the sober plumage of its pursuer is scarcely visible, passing often within a few feet of the spectator, and yet not a sound or a rustle will reach his ears. Sometimes the bird is said to strike its wings together over its back, so as to produce a sharp snapping sound, intended to express anger at the presence of the intruder. I never, however, heard this sound, though I have watched the bird so often.

Owing to the soft plumage with which it is clad, this bird, like the owls, looks larger than really is the case. It is between ten and eleven inches in length, with an expanse of wing of twenty inches, and yet weighs rather less than three ounces. Its large mouth, like that of the swallow tribe, opens as far as the eyes, and is furnished with a set of vibrissÆ or bristles, which remind the observer of the "whale-bone" which is set on the jaw of the Greenland whale.