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The first bone scrapers appropriate for scraping hides to make supple leather were found in Morocco dating to 90–120,000 years ago. [29] [30] 164 kya – 47 kya: Heat treating of stone blades in South Africa. [31] 135 kya – 100 kya: Beads in Israel and Algeria [32] 100 kya: Compound paints made in South Africa [33] [34] [35]
100: Menelaus of Alexandria describes spherical triangles, a precursor to non-Euclidean geometry. [69] 150: The Almagest of Ptolemy contains evidence of the Hellenistic zero. Unlike the earlier Babylonian zero, the Hellenistic zero could be used alone, or at the end of a number.
approximately 1893: The selenium phototube invention allows the conversion of brightness values into electrical signals. The principle is applied in wirephoto and television technology for a short time. Selenium is used in light meters for the next 50 years.
We’ve come a long way since humans started walking upright around 7 million years ago. The invention of stone tools in Ethiopia about 2.6 million years ago. The discovery of fire some years after.
The Upper Paleolithic, beginning approximately 40,000 years ago, saw the introduction of pressure flaking, where a wood, bone, or antler punch could be used to shape a stone very finely. [ 10 ] The end of the last Ice Age about 10,000 years ago is taken as the end point of the Upper Paleolithic and the beginning of the Epipaleolithic / Mesolithic .
From the first Apple computer to the COVID-19 vaccine, here are the most revolutionary inventions that were born in the U.S.A. in the past half-century.
The Patent Act of 1836 (Ch. 357, 5 Stat. 117) further clarified United States patent law to the extent of establishing a patent office where patent applications are filed, processed, and granted, contingent upon the language and scope of the claimant's invention, for a patent term of 14 years with an extension of up to an additional seven years.
Counting down to Christmas was done at least 100 years ago. This reminder appeared in the Daily Eagle on Dec. 4, 1924. The Pet and Novelty Shoppe announced they were opening at the end of the year ...