Letter from [?] to John Muir, 1907 Aug 14.

A. G. BARBER, PRES. & TREAS.F. A. BARBER, VICE PRES.FOUNDED 1889.INCORPORATED 1894.R. C. THOMPSON, ASST. TREAS.,MANAGER.W. W. SLADE, SECRETARY,SUPERINTENDENT.GLOBE OPTICAL COMPANYTHE HOUSE OF NEW ENGLANDMANUFACTURERS IMPORTERS EXPORTERSOPTICAL GOODS.MARLBORO BUILDING, 403 WASHINGTON ST.SURGICAL INSTRUMENTS,EYE, EAR, NOSE & THROAT.NEW ENGLAND AGENTSHARDYS OPHTHALMOMETERSDE-ZENGS LUMINOUSINSTRUMENTSSHUR-ON & SO-EASYMOUNTINGSMAKERS OFTORIC AND SPECIAL LENSES.INVISIBLE BIFOCALS.OPTICAL MACHINERYAND WORK BENCHES.GLOBE TABLES AND CABINETS.GLOBE EAR-PHONES.Los Angeles, Calif.August 14, 1907.John Muir,Martinez, Cal.Dear Mr. Muir:As you will see by this letter, I have returned from the Sierra Club outing, and am feeling finely; ready for another year of hard work.I am sending you under separate cover, catalogue of Microscopes and Accessories, made by the Bausch & Lomb Optical Co., of Rochester, New york. I wrote Mr. Edw. Bausch from camp, explaining what you wanted in the way of a Microscope, and a letter just received, advising Stands AH or BH, illustrated on pages 21 and 22 of catalogue.I should advise Stand BH4 as being the best all round Microscope for such work as you want. By reference to page 63, you will see that with the two-inch eye-piece, and the 2/3 objective, you will get 41 diameters, while with the one-inch eye-piece and 1/6 objective, you will get 585 diameters; thus giving you quite a range of power, with a very low priced Microscope.For the proper illumination of opaque objects, I should recommend using the new Vertical Illuminator, illustrated on page 72. This illuminator has recently been improved, and the price changed to $7.50.I believe I mentioned Dissecting Microscopes; the Y Stand illustrated on page 52, is very good, but you can get only 40 diameters magnification, and the lens giving\u27 this power is of short focus, with very small field.Pocket Magnifiers are illustrated on page 59, and as you will note, have recently been raised in price. These are not mounted in Aluminum, as you mentioned to me, but the German Silver is said to be stiffer and meanly as light.I shall be in San Francisco, Monday, the 19th inst., and if you would like to have me send you a Microscope and some Magnify-0391

Optical fibre nanowire technology and applications

A review of optical fibre nanowires and their applications is presented

Frequency stability of a self-phase-locked degenerate continuous-wave optical parametric oscillator

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Optically pumped terahertz laser based on intersubband transitions in a GaN/AlGaN double quantum well

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All-optical flip flop based on a symmetric Mach-Zehnder switch with a feed-back loop and multiple forward set/reset signals

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Ultra-Short Optical Pulse Generation with Single-Layer Graphene

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