Ubaldi, Guido

, was an eminent mathematician irt Italy, in the end of the sixteenth and early part of the seventeenth century, but no particulars are known of his life, nor when he died. The following occur in catalogues as his works: 1. “Mechanica,” Pis. 1577, fol. and Yen. 1615. 2. “Pianisphaeriorum universalium Theorica,” Pis. 1579, fol. and Col. 1581, 8vo. 3. “Paraphrasis in ArchimedisSquiponderantia,” Pis. 1588, fol. 4. Perspectiva,“ibid. 1600, fol. 5.” Problemata Astronomica,“Ven. 1609, fol. 6.” De Cochlaea," ibid. 1615, fol. ²