Note B. On the Songs of Birds. (pp. [48] and [149].)
As I have some musical knowledge, and have given some attention to the music of birds’ songs, it may be worth while to add one or two remarks on a subject which is as difficult as it is pleasing. I need hardly say that birds do not sing in our musical scale. Attempts to represent their song by our notation, as is done, for example, in Mr. Harting’s Birds of Middlesex, are almost always misleading. Birds are guided in their song by no regular succession of intervals; in other words, they use no scale at all. Their music is of a totally different kind to ours. Listen to a Robin in full song; he, like most other birds, hardly ever dwells for a moment on a single note, but modifies it by slightly raising or lowering the pitch, and slides insensibly into another note, which is perhaps instantly forsaken for a subdued chuckle or trill. The same quality of song may also be well observed in the Black-cap and in the Willow Warbler: the song of the latter descends in an almost imperceptible manner through fractions of a tone, as I have already observed on [page 48]. Strange as it may seem, the songs of birds may perhaps be more justly compared with the human voice when speaking, than with a musical instrument, or with the human voice when singing; and we can no more represent a bird’s song in musical notation, than the inflections of Mr. Gladstone’s voice when delivering one of his great speeches. The human voice when speaking is musically much freer than when singing; it is not tied down to tones and semitones.
If we remember that there are in our scale only twelve notes to the octave, and that between each of these an infinite number of sounds are possible, we shall get an idea of the endless variety which is open to the birds, and also, but in a less degree, to the human speaking voice.
Some birds, however, occasionally touch notes of our scale, and sometimes, though rarely, two in succession. The Cuckoo, as has often been noticed, sings a major or a minor third when it first arrives; not that the interval is always exact. The Thrush may now and then repeat two or three notes many times over, which almost, if not quite, answer to notes in our scale, usually from C to F of our treble scale. The Nightingale’s crescendo is a good instance of a single definite note; the song of the Chiff-chaff is perfectly plain and unvaried, but its two notes have never corresponded, when I have tested them, to an interval of our scale. Mr. A. H. Macpherson writes to me (Aug. 1886) that he has heard on the Brünig Pass, in Switzerland, three Chiff-chaffs singing at once, all in a different pitch. No. 1 was about a semitone above No. 2; No. 2 about a quarter of a tone above No. 3: the interval being the same in all cases. As my correspondent is a violin-player as well as an ornithologist, his observation may be taken as accurate. The Yellow-hammer’s curious song, which I examined carefully, may certainly be given in musical notation as keeping to a single note (often C or C sharp), but the concluding note of the song it is almost impossible to represent, for the pitch of the original note is raised or lowered by an interval varying from a minor third to less than a semitone. It is to be noted that in this species different individuals (according to my observation) have different modifications of the song; the Yellow-hammers in South Dorset (1886) struck me as singing in a different manner from our Kingham birds, though it would be almost impossible to describe the difference. I think I have noticed the same in the case of the Chaffinch. I have a note, made while travelling in Belgium, to the effect that the Chaffinches there did not seem to sing precisely the same song as ours in England. On the other hand, some observations which I made last year on the Chiff-chaff’s two notes in different localities led me to believe that the various birds were all singing at about the same pitch and in much the same manner.
There are many other interesting points connected with birds’ songs, e.g. the mechanism of the music; the song as a language; the entire absence of song in many birds, some of which, as the Crow, are among the most highly developed and intelligent; and the causes which operate in inducing song. It would be well if some well-qualified naturalist would investigate some of these points with greater attention than they have yet received. It would be hardly possible to find a subject of greater interest to the public, as well as to the savant.
Note C. Fables of the Kingfisher. ([p. 242].)
It may be worth while to suggest a possible explanation of the origin of the two curious and beautiful fables about this bird mentioned by Aristotle and Pliny, and current in antiquity. The first of these was, that for seven days before and seven days after the shortest winter day, the sea remained calm; during the first seven (says Aristotle) the bird builds her nest, and in the latter seven occupies herself with eggs and young. The second myth concerned the nest itself: “it is in shape like a cucumber, and larger than the largest sponge; the mouth is small—so small that the sea, as it rises, does not get inside it. It has, however, a great variety of holes, like a sponge, and appears to be made of the bones of a fish!” This last particular is curious, as we know it to be true of the Kingfisher’s nest; and it has led Prof. Sundevall to believe that Aristotle must have received some authentic report of the real nest, and have mixed it up with the mythical account. But his whole account shows plainly that he imagined the nest to be built on the rocks by the seashore, and perhaps even within reach of the waves.
Both these fables may, I think, have been built up on a slender basis of fact—the only fact which the Greeks seem to have known about the bird. Aristotle (Hist. Anim. v. 8. 4) tells us that the ἀλκύων was very seldom seen. “It is the rarest of all birds, for it is only seen at the setting of the Pleiades (about Nov. 9) and at the winter solstice; and it appears at seaports flying as much as round a ship, and then vanishing away.” Whether the bird is still seen in Greece only in late autumn and winter I cannot say; but Mr. Seebohm tells us (Brit. Birds, ii. 345) that in Eastern Europe it is compelled by the cold to migrate, some finding their way to Egypt, and therefore necessarily crossing the Ægean, or passing over Greece or the western coast of Asia Minor. I think it is a fair guess that those known to Aristotle were on their way from Thrace and Scythia to a warmer climate; and this hypothesis would explain not only their short stay, but their connection with the sea and harbours, and their mysterious character. Even supposing that a few haunted the Greek rivers at other times of the year, they would not be often seen there by a people not given either to sporting or to exploring out-of-the-way places; the one fact which would impress itself on the unscientific mind would be the sudden apparition in winter, and especially in mid-winter, of this little blue-green spirit about the harbours, and its as rapid disappearance.
If this be so, I think we have not far to seek for the origin of the two fables. Nothing being known of its nesting, it was assumed that it nested at or about the time when it appeared; and the not unfrequent calm and fine weather of mid-December would confirm the fancy, and give it a new mythical colouring. (The matter-of-fact philosopher does not of course allow that these fine days always occurred in his own experience; they are not always met, he says (v. 8. 3), in this country at the time of the solstice, “but they always occur in the Sicilian Sea.”) When this fable of the nesting-time had once established itself, it would be not very difficult to find a nest among the curiosities of the sea. So the little blue bird came to suffer “a sea-change, into something rich and strange,” through the careless fancy of the imaginative Greek.