Notes from Field and Study
Birds Through a Telescope
The season is approaching when the migration of birds may be studied to advantage through a telescope. A 2-inch hand glass may be used, though a higher power is preferable. It should be focused on the moon, across the surface of which the bird is seen passing.
September 3, 1887, at Tenafly, N. J., Mr. John Tatlock, Jr , and myself, using a 6½-inch equatorial, saw 262 birds cross the moon's disc between the hours of eight and eleven (The Auk, V, p. 37), and we have since repeated the observation.
Studies of this nature should throw much light on the question of 'highways of migration,' and at the same time furnish an idea of the number of birds passing through a given space during a given time; and, more particularly, they should tell us the height at which birds perform their nocturnal journeys.
Mr. Tatlock and myself solved this latter problem by a hypothetical assumption of the inferior and superior distances at which a bird would be visible. In this way we arrived at the conclusion that the birds seen were between one and three miles above the earth.
Until recently this theory has lacked confirmation, but I now learn from Dr. William R. Brooks, Director of Smith Observatory, at Geneva, N. Y. , that during the evening of May 23, 1899, while observing the moon through his 10⅛-inch refracting telescope, using a power of 100 diameters, he saw some forty birds cross the field of vision. Dr. Brooks states that from the distinctness of the image and the fact that from three to five seconds were required by each bird to cross the segment of the moon in the field of the telescope, he estimates the birds to have been distant about seven and a half miles, and further calculation, based on this estimate, places them about two miles above the earth. — Frank M. Chapman.
The Cardinal in Maine
This incident is vouched for by Mrs. L. M. N. Stevens, National President of the W C. T. U.
Several years ago, after the first snowfall at Stroudwater, Maine, Mr. Stevens hurried into the house one morning to ask his wife to come and see a handsome, but cold and hungry-looking, red bird, in a shrub near the door. Mrs. Stevens saw that it was a Cardinal Grosbeak, and, placing some food in a large cage, she set it near the bush. The Cardinal soon hopped inside, and was safely convoyed indoors under cover of a blanket. A happy season began. He was given the freedom of the room, and became very tame and companionable.
In the spring, as soon as the red bird grew restless and the weather mild, he was let loose, and flew away.
In the fall, with the first cold snap, came the Cardinal, to spend his second winter in the old home.
Again in the spring, when the restlessness re-appeared, Mrs. Stevens wanted to let the bird fly, but yielded to the judgment of her husband, who advised delay, lest cold and hunger overtake the little wayfarer. Nature, however, avenged the violation of instinct; in a few days the Cardinal drooped, refused to avail himself of liberty, and died. — Ella Gilbert Ives, Dorchester, Mass.
A Useful Bird
In speaking of the economic value of certain of our birds, a lecturer, quoting Professor Beal, said that in Iowa the Tree Sparrow was estimated to destroy 875 tons of the seeds of noxious weeds annually.
As reported in a local paper, this statement read: "The Tree or Chipping Sparrow destroyed, as discovered by scientific observation, 640,000 tons of the eggs and young of harmful insects."
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