On August 25th I made experiments on my left eye, with good measures, and on Aug. 26th ordered a cylindrical lens of Peters, a silversmith in the town, which I believe was never made.

By means of a convex lens it may be focused on the retina without accommodation (dotted lines).

Possibly I inherit my aunt's tendency to magnify into extraordinary proportions trifles which I look at through the double convex lens of a personal interest.

Presently it came in view through the upper lens, but did not obscure in the least the image of the stars which were then visible in the metacompass.

"We'll put on an enlarging lens, and get the camera close to them," explained Blake, who had had experience in taking several films of this sort for the use of schools and colleges.

" He handed the two photographs up to the judge, together with the 'Thumbograph,' the memorandum slip, and a powerful doublet lens with which to examine them.

The instruments employed are an eight inch Voigtlander photographic lens, reground by Alvan Clark & Sons, and Dr. Draper's 11 inch photographic lens, for which Mrs. Draper has provided a new mounting and observatory.

She who is called your wife is a clouded lens; she can receive the light only through John, who is her true spiritual husband, as Abby Fetters is your true spiritual wife!"

periscopic lens^; telescope, glass, lorgnette; spyglass, opera glass, binocular, binoculars, field glass; burning glass, convex lens, concave lens, convexo-concave lens^, coated lens, multiple lens, compound lens, lens system, telephoto lens, wide-angle lens, fish-eye lens, zoom lens; optical bench.

Two such lenses mounted with axes parallel and with curvatures varying in opposite directions produce a compound cylindrical lens, whose refraction in the direction of the axes is zero, and whose refraction in the meridian at right angles to this is at any point the sum of the refractions of the two lenses.

A diagram was drawn to show the manner of ascertaining the two Gauss points of a bi-convex lens, and a sheet exhibited in which the various kinds of lenses with their optical centers and Gauss points were shown.

The watery fluid occupying the space between the cornea and crystalline lens of the eye.

Newton surmounted this difficulty by laying a double convex lens, the radius of the curvature of each side of which was fifty feet, upon the flat surface of a plano-convex object-glass, and in the way he obtained a plate of air, or of space, varying from the thinnest possible edge at the centre of the object-glass where it touched the plane surface to a considerable thickness at the circumference of the lens.

Second, a pair of eye-glasses fitted with a powerful microscopic lens, able to distinguish good from evil.

The duplicate need not be equipped with as expensive a lens and shutter as the camera carried for work; 31/4 x 41/4 is a good size.

Between the two prisms a double refractive lens was now placed, in this case a double concave lens of selenite, when the same series of concentric rings observed with the film of air was obtained on the screen, only much more intense, while a wedge of selenite gave the bands of color in the same order as with the soap bubble.

It was, however, with some difficulty that he succeeded in finding the flower, which was so minute as almost to require a magnifying lens to observe it; it is a coniferous tree and was supposed by Mr. Cunningham to be allied to dacrydium.

Second, a pair of eye-glasses fitted with a powerful microscopic lens, able to distinguish good from evil.

The flaw in the diamond, the alloy in the gold, the stain in the purple, the blot upon the ermineall these are detected upon the instant; the value of the jewel is decreased, the price of the metal is deteriorated, the glory of the hue is tarnished, the purity of the mantle is sullied; and where minor imperfections may pass unperceived, a mighty social lens is for ever bearing upon the great.

Her ocean reflects the lights of heaven as in a mighty mirror, her atmosphere refracts them like a monstrous lens, the clouds and snow-fields combine them into white, the woods and flowers disperse them into colors.

Then he pulled over me a great movable lens as of a microscope, which concentrated the insupportable light.

periscopic lens^; telescope, glass, lorgnette; spyglass, opera glass, binocular, binoculars, field glass; burning glass, convex lens, concave lens, convexo-concave lens^, coated lens, multiple lens, compound lens, lens system, telephoto lens, wide-angle lens, fish-eye lens, zoom lens; optical bench.

[microscope components] objective lens, eyepiece, barrel, platform, focusing knob; slide, slide glass, cover glass, counting chamber; illuminator, light source, polarizer, [component parts of telescopes] reticle, cross-hairs.

The primrose on the river's brim he saw with a vision as clear as that of a photographic lens, but it remained to him a primrose and nothing more to the end.

A method was then referred to of making a rapid portrait lens cover a very large angle by pivoting at its optical center and traversing the plate in the manner of the pantoscopic camera.