{"product_id":"and-commerce-department-labor-of-s-u-bulletin-of-the-bureau-of-standards-1911-vol-7-classic-reprint-9780365903345","title":"Bulletin of the Bureau of Standards, 1911, Vol. 7 (Classic Reprint)","description":"Excerpt from Bulletin of the Bureau of Standards, 1911\u0026lt;br\/\u0026gt;\u0026lt;br\/\u0026gt;In the present experiments a ?uorite prism, a mirror spectro meter, and a new vacuum bolometer were used. The unknown metal was compared with a new silvered glass mirror of which the re?ecting power is known. The absolute value of the re?ectivity of the unknown metal was obtained by multiplying the observed re?ectivity by the re?ectivity of silver given in Table II (data from Hagen and Rubens). A Nernst glower was used as a source of radiation, which permitted making observations in the extreme blue and at my where the ?uorite prism is almost opaque. Since the glower is very narrow it is necessary to have a very accurate adjustment of its images, re?ected from the two mirrors upon the spectro meter slit, so as to avoid a systematic error in the re?ectivity. The observations in the infra-red were further verified by using a Nernst heater instead of the glower.","brand":"FB\u0026C LTD","offers":[{"title":"Default Title","offer_id":53723982299478,"sku":null,"price":0.0,"currency_code":"EUR","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0925\/5829\/5382\/files\/product_image_9780365903345_1.jpg?v=1781773474","url":"https:\/\/www.momoxbooks.com\/products\/and-commerce-department-labor-of-s-u-bulletin-of-the-bureau-of-standards-1911-vol-7-classic-reprint-9780365903345","provider":"momoxbooks","version":"1.0","type":"link"}