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{
    "localId": "7077466",
    "label": "Sky and Telescope Magazine",
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    "citationUrl": "https://catalog.archives.gov/id/7077466"
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{
    "id": "7077466",
    "sourceUrl": "https://catalog.archives.gov/id/7077466",
    "contentType": "document",
    "title": "Sky and Telescope Magazine",
    "description": "This item contains volume seven, issue three, number seventy-five of Sky and Telescope Magazine.",
    "citationUrl": "https://catalog.archives.gov/id/7077466",
    "collections": [
        "Russell W. Porter Papers",
        "Publications"
    ],
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    "url": "https://catalog.archives.gov/id/7077466",
    "naId": 7077466,
    "levelOfDescription": "item",
    "productionDates": [
        {
            "logicalDate": "1948-01-01",
            "month": 1,
            "year": 1948
        }
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{
    "seq": 19,
    "pageIndex": 0,
    "type": "photo",
    "url": "https://s3.amazonaws.com/NARAprodstorage/opastorage/live/66/774/7077466/content/arcmedia/dc-metro/XRWP/gallery/hd1-111196098-2012-021-pr.jpg",
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    "ocrText": "the instructions contained therein. The\ngrinding and polishing occupied 117 hours,\nNew Low Prices on PYREX\nPARABOLOIDAL MIRRORS\nand I was fortunate in parabolizing easily,\nReflecting Telescope Kits\nAluminized Pyrex, f/8, corrected\nas it was my first mirror.\nThese are the most complete kits on the\nmarket.\nto wave sodium light\nThe tube is of galvanized iron; the\nIn addition to the usual supply of abrasives,\nPLUS\nmounting of 2-inch pipe, with a 5-pound\nrouge, etc., you get the new, fast-polishing\nAluminized Elliptical Flat-1/4 wave\nlead counterweight. I assembled the 3x\ncerium oxide to save you hours of work.\n-inch\n$24.00 6-inch $40.00*\nTwo (2) finely polished plano convex lenses\nfinder from purchased lenses. The mirror\nto make a long focus eyepiece are also in-\n8-inch\n$85.00 10-inch $140.00\ncell is of wood, and adjustable.\ncluded in addition to an aluminized diagonal.\n12¹/2-inch\n$250.00\nYou can get a brass diagonal holder (spider)\nDOUGLAS CROSBY\n*With the 6-inch we supply, instead of the\nfor only $1.00 additional if ordered with a\nflat, a 1¹/4\" prism, silvered and lacquered\nStockton Springs, Me.\ntelescope kit. Prices quoted below are for\non the hypotenuse surface.\nPyrex telescope blank and plate glass tool.\n4\"\n$5.25\n6\"\n1¹/4\" Prism, angular correction 3\n$6.75\nS. F. Thorpe sends the following de-\n8\"\n$9.75\n10\"\n$16.75\nminutes, silvered and lacquered on\nscription of his testing apparatus, which\n12¹/²\"\nthe hypotenuse surface\n$3.00\nea.\n$31.75\nreceived the second prize at the Philadel-\nPostage Paid to ist and 2nd postal zones from\nOur years of experience in hand correct-\nN. Y. Add 5% 3rd and 4th zones, 10% 5th\ning, combined with production methods for\nphia convention exhibition (Sky and Tele-\nand 6th zones. Add 15% 7th and 8th zones.\ngrinding and polishing, make it possible\nscope, August, 1947):\nfor us to present these new reduced prices!\nSend for free catalog of optical supplies.\nAll prices plus postage.\nThe apparatus is a combination Foucault\nand Ronchi tester. The feature which\nDAVID WILLIAM WOLF\nL E M Optical Co.\n334 Montgomery St.\nBrooklyn 25, N. Y.\n69 S. Lexington Ave., White Plains, N. Y.\ndistinguishes this from other testing out-\nfits is the fact that the beams of light to\nand from the lens or mirror are separated\nby only 3/1,000 of an inch. When used as\na Foucault tester, the same edge that forms\nthe slit is also the knife-edge, therefore it\nis in perfect alignment. With this slit\nImmediate delivery\nopen wide, a small Ronchi grating may be\nplaced over the opening. Any change of\ndistance along the axis can easily be meas-\n3 and 4 inch\nured in thousandths.\nS. F. THORPE\nGlad-view Observatory\nRoute 4, Box 726\nPORTABLE\nLouisville, Ky.\nREFRACTORS\nFIREBALL OVER TENNESSEE\nAn extremely brilliant meteor was seen\nover most of Tennessee on November 16,\n1947, at 6:58 p.m. CST. The meteor was\nobserved nearly due south of Nashville,\nObjective lenses are pre-\ntraveling in a northerly direction. A1-\nFIRST QUALITY DOUBLE OBJECTIVE LENS,\ncision ground of the very\nthough most reports came from untrained\nobservers, there seems no doubt that the\nLOW POWER FINDER with CROSSHAIRS,\nhighest quality crown and\nobject moved relatively slowly and burst\nflint optical glass, and cor-\nclose to Shelbyville, Tenn.; many observ-\nSTAR DIAGONAL (or prismatic inverter\nrected for chromatic and\ners near that town heard the characteris-\nfor terrestial work), RACK AND\nspherical aberrations.\ntic rushing sound and explosion made by\nthe bursting of a meteor, and windows\nPINION FOCUSING, 5 FOOT\nBoth instruments reveal\nrattled in the vicinity. During most of\ndetails as found on Mars,\nHARD MAPLE TRIPOD,\nits path, the meteor was many times\nJupiter, and Saturn with\nbrighter than the full moon, and at the\nALUMINUM TUBE\nunusual richness and bril-\ntime of the burst most observers reported\nit as bright as full daylight. No train of\nliance. These and other\nany sort was reported.\nportable reflecting and\nAs the explosion occurred about one\n3 INCH COMPLETE\nminute after the meteor was seen, its\nWITH 45, 90, 180\nrefracting typesare avail-\nheight at the burst must have been less\nPOWER EYEPIECES\nable immediately; de-\nthan 12 miles. Its brightness suggests a\n$265\nscriptive folders sent on\nmass in excess of one ton, but as yet no\nrequest. Inquiries on\nmeteorites or crater have been found. Sev-\n4 INCH COMPLETE\npermanently mounted\neral near accidents were reported by mo-\ntorists frightened by the brilliant flash.\nWITH 60, 120, 240\ninstruments for college\nPOWER EYEPIECES\nAn airline pilot saw the explosion when\nand private observa-\nhe was about 40 miles west of Nashville,\n$435\ntories are invited.\nand it appeared so close that he abruptly\nchanged the Memphis-Nashvill course of\nthe plane to avoid a crash.\nFurther observations of this meteor are\nhighly desirable. Persons who saw it are\nasked to communicate with Dr. Carl K.\nTinsley\nlaboratorie's\nSeyfert, Barnard Observatory, Vanderbilt\nUniversity, Nashville, Tenn. Report at\n2526 GROVE\nFOLDER\nleast the place of observation, the direction\n(*\nBERKELEY\nSENT ON\nand elevation of the point in the sky where\nCALIFORNIA\nREQUEST\nthe meteor was first seen, similar directions\nfor the point where the meteor exploded.\nReasonably accurate charts of the fire-\nPrice subject to\nchange without notice\nball's path among the constellations are\nalso of considerable value.\nJanuary, 1948, SKY AND TELESCOPE 77"
}