ONE of the best places to study birds is from behind the blinds of a conveniently-placed window, where one can see without being seen.

My window one July looked into the tops of tall spruce trees, relieved here and there by a pine, a birch, or a maple. This was the home of the most fascinating and the most bewildering of feathered tribes, the warblers, and a rugged old spruce tree was a favorite "Inn of Rest" for every bird in the vicinity.

In all the years that I have known birds I have carefully avoided becoming interested in warblers, so tiny, so restless, so addicted to the upper branches, so every way tantalizing to study. But here, without intention on my part, fate had opened my windows into their native haunts, even into the very tree-tops where they dwell. "He strives in vain who strives with fate." After one protest I succumbed to their charms.

My principal visitor was a beauty, like most of his distinguished family, having a bright yellow head, set off by a broad black band beginning at the throat and running far down the sides, and he bore the awkward name "black-throated green warbler."

A bewitching and famous singer is this atom in black and gold. And not only is his song the sweetest and most winning, but the most unique, and—what is not generally known—the most varied.

The song that has been oftenest noticed, and is considered characteristic of the species, is sometimes syllabled as "trees, trees, beautiful trees," sometimes as "hear me Saint Theresa." But in my intimate acquaintance with some of the family that July I noted down from my window alone eight distinctly different melodies. My special little neighbor, who spent hours every day in the old spruce, sang the regulation carol of his tribe, but he also indulged in at least one other totally unlike that. Those two I have heard and seen him sing, one directly after the other, but he may have had half a dozen arrangements of his sweet notes.

Sometimes the mate of my spruce-tree neighbor appeared on the tree, going over the branches in a businesslike way, and uttering a loud, sharp "chip."

One morning there suddenly broke out in the old spruce a great clatter of "tick-et! tick-et!" in the voice of a nestling. I snatched my glass and turned it at once upon a much-excited warbler, my black-throated green. He was hopping about in a way unusual even with him, and from every side came the thread-like cries, while the swaying of twigs pointed out a whole family of little folk, scrambling about in warbler fashion and calling like bigger bird babies for food. They were plainly just out of the nest, and then I studied my spruce-tree bird in a new role, the father of a family.

He was charming in that as in every other, and he was evidently a "good provider," for I often saw him after that day going about in great anxiety, looking here and there and everywhere, while a small green worm in the beak told plainly enough that he was seeking his wandering offspring.

During the remainder of the month I frequently saw, and more frequently heard, the little family as they followed their busy parents around on the neighboring trees.

One day I noted the singer flitting about the top of the spruce, singing most joyously, and almost as constantly as before the advent of the nestlings, while the mother was hurrying over the lower branches of the same tree, collecting food for one youngster. Suddenly the song ceased, and the tiny papa joined the family party below, and addressed himself with his usual energy to the business of filling that greedy mouth.

Over and under and around and through the branches he rushed, every few seconds returning to stuff a morsel into the always hungry mouth, till he actually reduced that infant to silence, and then he slipped away, returned to his tree top, and resumed his lovely "tee-tee-tweetum!"

Somewhat later I heard the baby black-throats at their practice, droll, quavering attempts to imitate the musical song of their father. They soon mastered the notes, but the spirit was as yet far beyond them.

This happy life went on before my window till, almost at the end of July, a heavy fog swept in one evening from the ocean, and when, the next day, a cool north wind blew it back whence it came, it seemed to take the whole tribe of warblers with it. August was now upon the threshold, and in the bird world at least

"Summer like a bird had flown."