Their singing is always an intended speech; and it is comical enough that there should be thus in the world so numerous a nation which never speak otherwise but tunably and musically. But, in short, what do those birds say? The question should be proposed to Apollonius Tyaneus, who boasted of understanding their language. As for me, who am no diviner, I can give you no more than probable conjectures. Let us take for our example the magpie, which is so great a chatterer. It is easy to perceive that her discourses or songs are varied. She lowers or raises her voice, hastens or protracts the measure, lengthens or shortens her chit-chat; and these evidently are so many different sentences. Now, following the rule I have laid down, that the knowledge, desires, wants, and of course the expressions of beasts, are confined to what is useful or necessary for their preservation, methinks nothing is more easy than at first, and in general, to understand the meaning of these different phrases.”--_Dublin University Magazine._ * * * * * ATMOSPHERIC RESISTANCE ON RAILWAYS.--In Dr Lardner’s third lecture on railways at Manchester, he detailed a variety of experiments made in order to ascertain the source of resistance. “He found that an enlarged temporary frontage constructed with boards, of probably double the magnitude of the ordinary front of the train, caused an increase of resistance so trifling and insignificant as to be entirely unworthy of account in practice. Seeing that the source of resistance, so far as the air was concerned, was not to be ascribed to the form or magnitude of the front, it next occurred to him to inquire whether it might not arise from the general magnitude of the train front ends, top and all. An experiment was made to test this. A train of waggons was prepared with temporary sides and ends, so as to represent, for all practical purposes, a train of carriages, which was moved from the summit of a series of inclined planes, by gravity, till it was brought to rest; it was next moved down with the high sides and ends laid flat on the platform of the waggons, and the result was very remarkable. The whole frontage of the latter, including the wheels and every thing, a complete transverse section of the waggons, measured 24 feet square, and with the sides and ends up, so as to present a cross section, it amounted to nearly 48 square feet. The uniform velocity attained on a plane of 1 in 177, without the sides up, was nearly 23 miles an hour; whereas, with the sides up, it was only 17 miles an hour; so that, as the resistance would be in proportion to the square of the velocity, other things being the same, there would be a very considerable difference, due to that difference of velocity. Then, at the foot of the second plane, while the sides were down, an undiminished velocity remained of 19½ miles an hour, whereas, with the sides up, it was reduced to 8½ miles an hour; so