eventually, owing to rough weather making it unsafe to land the shed, it was a week later than the previous year when we put it up. The shed itself was quite satisfactory, but a new focal-plane shutter, in which I had invested four pounds, was apparently unfinished when finally delivered a day or two before I started, and ruined most of my exposures. The weather only permitted three watches at the eyrie, and, to crown all, the young left it a week sooner, as, owing to there only being two of them, they were more abundantly fed and developed more rapidly, a fact I had previously noted with ravens.
In 1912 the shed was erected within two days of hatching, and as I had invited several bird-watchers to join me, we were enabled, by a system of daily reliefs, to have the birds under constant observation for thirteen days and nights. Of the notes thus acquired I am including those of my friend, H. B. Booth, both because they give a fair idea of life in the shed and because I think they will make it obvious how valuable such a contrivance is for those who, untrammelled by the cares of photography, wish to use it for simply observational purposes. Its cost, however—the material alone came to over three pounds—will, no doubt, prevent its adoption generally by ornithologists, who seem to prefer the inexpensive blowpipe and its immediate and tangible results.
