The steam-engine is a compound machine which exerts a moving force, and is the primum mobile or first moving power to give motion to other machines, mills, or engines. |
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Some religious orders celebrated Mass according to rites of their own, dating from more than 200 years before the papal bull Quo primum. |
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These liturgical rites have an antiquity of at least 200 years before 1570, the date of Pope Pius V's Quo primum, and were thus allowed to continue. |
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The drawings show the Ptolemaic system of nested spheres, with one circle inside the other, ending in the Primum Mobile. |
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