{"product_id":"vintage-cenco-wallace-replica-rowland-plane-diffraction-grating-brass-stand","title":"Vintage Cenco Wallace Replica Rowland Plane Diffraction Grating Brass Stand","description":"\u003ch3\u003eOverview\u003c\/h3\u003e\n\u003cp\u003eA vintage diffraction grating from the Central Scientific Company (Cenco) of Chicago, mounted in a brass frame on a brass base. The frame holds a glass plate, and the printed label reads \"Wallace's Replica of Rowland's Plane Diffraction Grating\", \"Lines to the inch\" and \"Central Scientific Company, Chicago, Ill.\", with \"10,160\" written in by hand in red ink. The frame has mitered corners and sits between two side screws on the base. It is a small, solid piece for a science instrument collection, a bookshelf or a desk.\u003c\/p\u003e\n\u003ch3\u003eBackground\u003c\/h3\u003e\n\u003cp\u003eDiffraction gratings split light into its colors and were standard equipment in school and college physics labs. Henry Rowland of Johns Hopkins University was known for his finely ruled gratings, and replica gratings copied from ruled originals made them affordable for teaching. Central Scientific Company was a Chicago supplier of laboratory equipment. This one is brass and glass and weighs 7.1 oz.\u003c\/p\u003e\n\u003ch3\u003eCondition\u003c\/h3\u003e\n\u003cp\u003eGood vintage condition. The brass has an even, dark patina with light wear, and there are old scratched marks on the underside of the base. The grating film shows some clouding and toning, and the label is legible with light age toning. Please see all photos.\u003c\/p\u003e\n\u003ch3\u003eDimensions \u0026amp; Weight\u003c\/h3\u003e\n\u003cp\u003eIt is 2.4 inches high, 2.2 inches wide and 1.5 inches deep (H x W x D). It weighs 7.1 oz.\u003c\/p\u003e\n\u003ch3\u003eShipping\u003c\/h3\u003e\n\u003cp\u003eFree standard shipping within the US, packed securely.\u003c\/p\u003e","brand":"Belle Afrik Arts","offers":[{"title":"Default Title","offer_id":60265908338974,"sku":"BA-1378","price":95.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/1081\/5176\/7326\/files\/WhatsAppImage2026-10-11at11.10.02.jpg?v=1791732136","url":"https:\/\/belleafrikarts.com\/products\/vintage-cenco-wallace-replica-rowland-plane-diffraction-grating-brass-stand","provider":"Belle Afrik Arts","version":"1.0","type":"link"}