One American invention, or discovery, has gone far towards paying back all that the new continent owes to the old civilizations. The cradle of artificial _anaesthesia_--man's independence of the tyranny of pain--must be looked for at the side of the Cradle of Liberty. Never was a greater surprise than the announcement of this miraculous revelation to the world. One evening in October, 1846, a professional brother called upon the writer of this paper. He shut the door carefully, and looked nervously around him. Then he spoke, and told of the wondrons results of the experiment which had just been made in the operating-room. "In one fortnight's time," he said, "all Europe will be ablaze with this discovery." He then produced and read a paper that he had just drawn up for a learned society of which we were both members, the first paper ever written on this subject. On that day not a surgeon in the world, out of a little New-England circle, made any profession of knowing how to render a patient quickly, completely, pleasantly, safely insensible to pain for a limited period. In a few weeks every surgeon in the world knew how to do it, and the atmosphere of the planet smelt strong of sulphuric ether. The discovery started from the Massachusetts General Hospital, just as definitely as the cholera started from Jessore, to travel round the globe. The advance of our civilization is still more strongly marked by the number and excellence of musical instruments, especially pianos, which are made in this country. It would hardly be an exaggeration to say that the piano keeps pace with the plough, as our population advances. More striking evidence than even this is found in the fact that the highest grade of the highest instruments used for scientific research is produced by our artisans. One of the two largest telescope-lenses in the world is that made by Mr. Clark, of Cambridge, whose reputation is not confined to our own country. The microscopes of Mr. Spencer, which threw those of the Continent into the shade at once, and challenged competition with the work of the three great London opticians, were made in a half-cleared district of Central New York, where, in our pilgrimages to that Mecca of microscopists, Canastota, we found the shrine we sought in the midst of the charred stumps of the primeval forest. While Mr. Quekett was quoting Andrew Ross, the most famous of the three opticians referred to, as calling "135 deg. the largest angular pencil that can be passed through a microscopic object-glass," Mr. Spencer was actually making twelfths with an angle of more than 170 deg.. Those who remember the manner in which the record of his extraordinary success was deliberately omitted from the second edition of a work which records the minutest contrivance of any English amateur,--the first edition having already mentioned the "young artist living in the backwoods,"--will recognize in it something of the old style in which