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Broschürt. Obr.-, [WES69]. // Deu 300g.

Zustand: Good. Most items will be dispatched the same or the next working day. A copy that has been read but remains in clean condition. All of the pages are intact and the cover is intact and the spine may show signs of wear. The book may have minor markings which are not specifically mentioned.

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Paperback. Zustand: Good. First Edition. "Deals with tattooing practices among the Cree, with particular emphasis upon the Plains divisions. Also contains comparative data from the Ojibwa and Assiniboine with whom the Crees camped and hunted. These tribes often adopted each other's customs to the point where it became difficult to distinguish one from another." - page 3. 24 pages. Bibliography, diagrams, map and reproductions of black and white photos. Printed upon glossy stock. Unmarked with moderate wear. A sound copy of this informative reference. Strathern 2042. ; Glenbow-Alberta Institute Occasional Paper No. 6 (Six); 8vo - over 7¾" - 9¾" tall; Tattooing Practices of the Cree Indians: Glenbow-Alberta Institute Occasional Paper No. 6 (Six) Tattoo History Native Peoples Plains Ojibwa Assiniboine Customs Tattoo History Native Peoples North America.

Leipzig, Johann Ambrosius Barth, 1867. Contemp. hcalf, raised bands, gilt spine with gilt lettering. A few scratches to binding. In "Annalen der Physik und Chemie. Hrsg.von Poggendorff", Bd. 99. (Entire volume offered). (2),X,652 pp. and 4 folded engraved plates. Weber & Kohlrausch's paper:pp. 10-25. First appearance of this importent paper, the results of which Maxwell later used as a crucial support for his electromagnetical theory of light.".The velocity of light c were measured by W. Weber and R. Kohlrausch in 1855 (the paper offered). They used an electrometer to determine the charge of a condnsor in electrostatic units, and a ballistic galvanometer to measure the same charge in electrodynamic units. The resulting value for c was in good agreement with that obtained by Fizeau in 1849, and Maxwell accordingly felt entitled to identify light and electromagnetic vibrations. This conclusion recalls Newton's identification of gravity with universal attraction: it was not only because they obeyed the same formal law, but also because both led to the same mathematical results, that Newton saw fit to combine them."(Taton, Réne in "History of Sciencein The Nineteenth Century", p. 163).

Halle, Rengerschen Buchhandlung, 1801. Without wrappers as published in "Annalen der Physik. Herausgegeben von Ludwig Wilhelm Gilbert", Bd. 7, Viertes Stück. The entire issue offered (=Heft 4). Pp. 387-528. Ritter's announcement p. 525. With titlepage to volume 7. Clean and fine. Titlepage a bit shavedin inner margin. First printing of Ritter's announcement of his discovery of ultraviolet light in a halfpage letter addressed to Gilbert's Annalen. With that discovery, it became clear that visible light represents no more than a fraction of a continous spectrum.A year earlier, in 1800, William Herschel discovered infrared light. This was the first time that a form of light beyond visible light had been detected. After hearing about Herschel's discovery of an invisible form of light beyond the red portion of the spectrum, Ritter decided to conduct experiments to determine if invisible light existed beyond the violet end of the spectrum as well. He had heard that blue light caused a greater reaction in silver chloride than red light did. Ritter decided to measure the rate at which silver chloride reacted to the different colors of light. He directed sunlight through a glass prism to create a spectrum. He then placed silver chloride in each color of the spectrum and found that it showed little change in the red part of the spectrum, but darkened toward the violet end of the spectrum. Johann Ritter then decided to place silver chloride in the area just beyond the violet end of the spectrum, in a region where no sunlight was visible. To his amazement, this region showed the most intense reaction of all. This showed for the first time that an invisible form of light existed beyond the violet end of the visible spectrum. This new type of light, which Ritter called Chemical Rays, later became known as ultraviolet light or ultraviolet radiation (the word ultra means beyond). - Parkinson, Breakthroughs: 1801 P.