oing by looking into it, and the apple which gave relief to the
most desperate sufferings only by inhalation of its fragrance. The
railroad-car, the telegraph, and the apple-flavored chloroform could and
do realize, every day,--as was stated in the passage referred to, with
a certain rhetorical amplitude not doubtfully suggestive of the
lecture-room,--all that was fabled to have been done by the carpet, the
tube, and the fruit of the Arabian story.

All these inventions force themselves upon us to the full extent of
their significance. It is therefore hardly necessary to waste any
considerable amount of rhetoric upon wonders that are so thoroughly
appreciated. When human art says to each one of us, I will give you
ears that can hear a whisper in New Orleans, and legs that can walk six
hundred miles in a day, and if, in consequence of any defect of rail
or carriage, you should be so injured that your own very insignificant
walking members must be taken off, I can make the surgeon's visit a
pleasant dream for you, on awaking from which you will ask when he
is coming to do that which he has done already,--what is the use of
poetical or rhetorical amplification? But this other invention of _the
mirror with a memory_, and especially that application of it which has
given us the wonders of the stereoscope, is not so easily, completely,
universally recognized in all the immensity of its applications and
suggestions. The stereoscope, and the pictures it gives, are, however,
common enough to be in the hands of many of our readers; and as many of
those who are not acquainted with it must before long become as familiar
with it as they are now with friction-matches, we feel sure that a few
pages relating to it will not be unacceptable.

Our readers may like to know the outlines of the process of making
daguerreotypes and photographs, as just furnished us by Mr. Whipple, one
of the most successful operators in this country. We omit many of those
details which are everything to the practical artist, but nothing to
the general reader. We must premise, that certain substances undergo
chemical alterations, when exposed to the light, which produce a change
of color. Some of the compounds of silver possess this faculty to a
remarkable degree,--as the common indelible marking-ink, (a solution of
nitrate of silver,) which soon darkens in the light, shows us every day.
This is only one of the innumerable illustrations of the varied effects