BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 0

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 1

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 2

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 3

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 4

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 5

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 6

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 7

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 8

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 9

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 10

BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953, US $475.00 – Picture 11

Bausch & Lomb Vintage Model Li-2 Petrographic Polarizing Pol Lab Microscope 1953

US $475.00

Hamilton, Montana, United States
Jan 30th

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Payment | Shipping BAUSCH & LOMB VINTAGE MODEL LI-2 PETROGRAPHIC POLARIZING POL LAB MICROSCOPE 1953 Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album Click to View Image Album BAUSCH & LOMB VINTAGE MODEL LI-2 DYNOPTIC PETROGRAPHIC POLARIZING LABORATORY MICROSCOPE – 1953 You are invited to purchase a nice vintage Bausch & Lomb Optical Company Model “LI-2” Dynoptic Petrographic Polarizing (POL) Monocular Laboratory Microscope. This is a fully functional intermediate series research grade laboratory microscope that is still fully capable of both qualitative and quantitative petrographic analyses of thin mineral sections and crystals, etc. This microscope bears the name of the manufacturer on the front face of the body tube, “B&L, Bausch & Lomb Incorporated, Rochester, N.Y., USA.” The instrument also bears a serial number, which is found on the underside of the limb, “DB3838” (see close-up image). This serial number dates this instrument to the year 1953. As is mentioned in the 2003 publication entitled, “The Petrographic Microscope: Evolution of a Mineralogical Research Instrument” by Daniel E. Kile, petrographic microscopes and accessories are comparatively rare. For every 100 biological microscopes manufactured, perhaps only one was made for petrographic use. In addition, petrographic microscopes are much more complicated than biological microscopes. Although the magnifying powers used are comparable and not so great, there are attached appliances for special examination of mineral or chemical substances that require very careful adjustment. This vintage Bausch & Lomb specialty microscope is equipped with such special features such as a rotating circular stage with vernier scale, a flip-in/flip-out Bertrand Lens, a flip-in/flip-out Polaroid analyzer, a rotating substage condenser-Polaroid polarizer, a centerable nosepiece with a quick-change adaptor for objective lenses, and a port above the objective holder to accommodate special optional accessories (compensators / sliders) needed for the microscopic analysis of minerals (Note: No compensators are included and none were originally included with this model instrument). Accompanying this listing from my personal collection of antique and vintage microscope catalogues is a cut from the 1970 edition of B&L’s “Catalogue of Polarizing Microscopes” that shows this model microscope. It is included here for comparison with the featured instrument. The similarities to the featured instrument are readily apparent. Petrographic polarizing microscopes first made their appearance in Europe and the UK in the latter decades of the 19th Century. Such prominent microscope manufacturers as Nachet, Fuess, Lietz, Leiss, Zeiss, Reichert, Siebert, Watson, Swift & Son and others all produced their own versions of this specialty instrument. American microscope manufacturers soon followed suit. In the late 1890s Bausch & Lomb entered into a special cooperative business relationship with Zeiss in Germany, which allowed them to acquire some of the special technical expertise needed to produce a new line of petrographic polarizing microscopes in the USA. In addition, B&L used the design of Dr. Fred E. Wright from the Carnegie Institution of Washington, D.C. to produce their own unique line of petrological polarizing microscopes. The end result was the introduction of the L series of Petrographic Polarizing Microscopes. This line initially included the LCH (Laboratory Model) and the LD (Research Model) with the familiar “Jug-handle” limb that was popular during the early decades of the 20th Century. By the early 1950s, the designs had become more refined and the line was renamed the Dynoptic Polarizing Microscope series, which involved the use of Polaroid analyzers and polarizers instead of crystal prisms. About the word “Dynoptic,” B&L stated in their literature: “The word DYNOPTIC has been chosen to be indicative of the mechanical and optical excellence with which this series of microscopes has been endowed.” Offered here is an early example of a Model LI-2 Dynoptic Petrographic Polarizing Microscope from the mid-20th Century. For the vintage / antique microscope collector this B&L Model LI-2 Dynoptic Petrographic Polarizing Microscope represents one of several significant advances in the evolution and design of this specialty microscope offered by the US based Bausch & Lomb Optical Company. As such, it will be a most welcome and valuable addition to any vintage / antique microscope collection, especially one with an emphasis on petrographic polarizing microscopes. As an added bonus, it still is 100% fully functional, and it can still be used in a modern petrographic laboratory to conduct both qualitative and quantitative analyses of mineral samples. Don’t miss this opportunity to make this sophisticated scientific instrument your own. DETAILED DESCRIPTION: This microscope is built upon B&L’s modern Dynoptic stand that consists of a heavy elongated horseshoe-shaped base with an integral short split pillar that rises from the base and terminates in a trunnion joint. This joint supports the rest of the microscope, including the widely sweeping -continental style arm, the stage, the body tube and the substage assembly. The trunnion joint allows the microscope to be tilted at any angle from the vertical to allow for the comfortable viewing of specimen slides atop the stage. Coarse focus is by rack and pinion. Fine adjustment is by a pair of micrometer knobs found on either side of the trunnion joint. The knob on the right side has a vernier scale with the inscribed notation that 1 division is equal to 0.001mm in the fine focus of the instrument – a very precise level of fine focus on any microscope. The microscope is equipped with a pre-centered 130 mm diameter ball-bearing circular rotating stage with an engraved vernier scale on the periphery. The stage circumference is graduated in single degrees with each tenth line numbered. The top of the stage is equipped with a pair of slide clips. Below the stage is a relatively complex substage apparatus consisting of a condenser/ polarizer assembly with an integral iris diaphragm, heat-adsorbing filter, Polaroid polarizer and two condensing lenses. The condenser, which B&L called their “verti-slide variable focus condenser,” has a variable focus feature from 0.08 N.A. to 1.25 N.A. without the inconvenience of removing or swinging-out the upper lens element. The polarizer is rotatable through 360 degrees and is graduated at each 45-degree interval. Under the substage condenser / polarizer unit is a 54mm diameter plano-concave mirror on a removable double prong mirror support that completes the substage illumination system. NOTE: The mirror can also be removed from the stand and a more modern electrical or LED illuminator can be used to provide illumination. The body tube of this microscope is much more complex than that found on a conventional biological microscope. At the top of the body tube is an ocular holder with a slot in its upper edge. This feature is designed for fixing the azimuth of cross hair eyepieces used on the instrument. A single 5x eyepiece (without a cross hair) is included with this microscope. About a third of the way down the body tube below the eyepiece holder is a flip-in/flip-out fixed focus Bertrand lens that is used with a 45x objective (not included) for the examination of interference figures of mineral specimens. A hand knob on the right side of the instrument controls its position – either into or out of the optical path. It is also sealed in place to prevent dust entry into the body tube. At the approximate lower third of the body tube is a flip-in/flip-out Polaroid analyzer. It too is controlled by a hand knob found on the right side of the body tube allowing it to be moved into or out of the optical path with a quick flip of the wrist. Below the analyzer is a port that can be opened or closed with a lever and that is used to accommodate polarizing sliders/compensators. Note: No compensators were originally included with this model microscope and none are included with this instrument. Under the slider port is a special fitting with a locking mechanism for the objective lenses. A single B&L 20x objective lens on a special quick exchange adaptor with centering pins is included with this instrument. NOTE: No centering tools are provided. However, if desired, the adjustments can still be made using a pair of small pliers. This microscope stands about 13.5 inches tall and weighs about 12 pounds – a relatively heavy vintage microscope. STATEMENT OF CONDITION: NOTE: The accompanying images, which were captured under ambient light conditions, are a part of this statement of condition. Please take the time to view all of the images so you can confirm the condition of the instrument and so you will know exactly what you will be getting should you prove to be the proud new owner of this vintage B&L Model LI-2 Dynoptic Petrographic Polarizing microscope. In summary, this microscope is in very good to excellent cosmetic, mechanical and optical condition. As the accompanying images attest, the black lacquered metal and chromed parts of this instrument are in excellent condition with no significant blemishes to report. However, this microscope appears to have been part of an inventory of a college or university. So, it has an institutional serial number engraved into the heel of the rear of the horseshoe foot. The optics associated with this microscope are in excellent condition. Both the eyepiece and the objective lens that come with the instrument are free of any optical defects. The Bertrand lens and the substage condenser with polarizer are all without any internal optical defects. However, the analyzer appears to have some lens fungus present, but this age defect does not appear to adversely impact the images at the eyepiece. In fact, the views under polarized light are quite stunning, as the accompanying images of thin sections of the minerals Pyroxenite from the Canary Islands of Spain and Hornblende Granite from Saxony will testify. These images were captured using the B&L 20x objective mounted on this very microscope. Note the exceptional fine details evident in these images. The plano-concave mirror is in excellent condition with no defects on either side. Mechanically, both the coarse and fine focus mechanisms work smoothly and flawlessly on this instrument. The stage rotates smoothly, but it is missing the screw for the arrest mechanism. The substage illumination apparatus works perfectly and it provides excellent illumination to the stage. The iris diaphragm in the substage condenser came to us missing the control lever. We replaced it with a long brass screw, which serves the same function as the original control lever. Overall, this is a very nicely preserved example of a vintage Bausch & Lomb Model LI-2 Dynoptic Petrographic Polarizing Microscope from the mid-20th Century. It is certainly worthy of any vintage / antique microscope collection. And, should one choose to do so, it can still be used to this day for the serious qualitative examination and detailed quantitative analysis of thin mineral sections and other suitable transparent specimens under polarized light. PURCHASE: THE MONTANA LOGGER is very pleased to offer this Bausch & Lomb Model LI-2 Dynoptic Petrographic Polarizing Microscope for a very reasonable “Buy-It-Now” cost. We will also entertain reasonable offers for this superb fully functional vintage precision instrument. NOTE: WE WARMLY WELCOME INTERNATIONAL BIDDERS/BUYERS. WE SHIP WORLDWIDE. PAYMENT: Payment via PayPal is due within 3 days of purchase. Prompt payment is always very much appreciated. Payment Back to Top I accept the following forms of payment: PayPal Shipping & Handling Back to Top US Shipping $0.00 USPS Parcel Post® International Shipping $95.67 USPS Priority Mail International (Worldwide) $74.82 USPS Priority Mail International (Canada) FREE scheduling, supersized images and templates. Get Vendio Sales Manager. Make your listings stand out with FREE Vendio custom templates! FREE scheduling, supersized images and templates. Get Vendio Sales Manager. Over 100,000,000 served. Get FREE counters from Vendio today! Click Here. Double your traffic. Get Vendio Gallery - Now FREE!

Condition	Seller refurbished : An item that has been restored to working order by the eBay seller or a third party not approved by the manufacturer. This means the item has been inspected, cleaned, and repaired to full working order and is in excellent condition. This item may or may not be in original packaging. See the seller’s listing for full details.
Seller Notes	“This vintage B&L Model LI-2 Petrographic POL Microscope is in very good to excellent cosmetic, mechanical and optical condition and can still be used for serious microscopic investigations to this day.”