VOL. XXIV. 3 PHILOSOPHICAL TRANSACTIONS. 137 



p. 6 ; astroites, p. 36, 3g. Of the sea-shells that he gathered on these moun- 

 tains, the most considerable are the nerita, p. 26 ; auris marina fossilis, p. 58 ; 

 umbilicus marinus, p. 24; concha tellinoides, p. 21 ; conchas margaritiferae 

 fragmenta, p. 55 ; conchula echinata, p. 49 ; pectunculus parvus capillaribus 

 striis notatus, p. 23 ; pecten dense striatus, ibid ; chamafossilis, p. 55. In this 

 shell he observes there were discernible the vestigia of the muscles by means of 

 which the animal adhered to the shell. Nor ought we to omit the echinus 

 spatagus, p. 61 ; the asteriae, p. 2; the entrochi, p. 4, &c. ; two joints of the 

 claw of a lobster struck out of a piece of stone, p. 27 ; and a piece of a shell 

 of a crab, of that sort that is called the molucco-crab, lodged in a very hard 

 sort of stone, p. 65. ^ 



///. De Locis solidis secunda Divinatio Geometrical in quinque Libros Injuria Tern' 

 porum amissos, ^ristcei Senioris Geometra, Autore Kincentio Fivianiy Mag- 

 ni Duds Etruria Mathematico Primario, et Regalis Societatis Londini Sodali. 

 Opus Conicum in Lucem prolatum, Ann. 1701, Fol. N° 29I, p. 1607. 



Vincentio Viviani, who was 80 years old when this book was published, and 

 the only surviving scholar of the famous Galileo, was ever since the year J 642 

 employed by the great Dukes of Tuscany in directing the fortifications of their 

 dominions, superintending their buildings, the banks of the rivers, and other 

 public works ; so that he complained that he had not leisure to prosecute his 

 inventions in geometry, which he made in his younger days, of which this book 

 is one. 



His other works are these. In the year 1659, he published in folio, De 

 Maximis et Minimis Divinatio Geometrica in Quintum ApoUonii Librum. In 

 the year 1692 he published in Italian, Formazione e Misura di Tutti i Cieli, in 

 consequence of an aenigma architectonicum which under a fictitious name he 

 had proposed in the beginning of that year, in which divers learned men con- 

 cerned themselves.* These are all he has published in mathematics besides 

 this book, and two small pieces, containing the solutions of some problems 

 proposed by French mathematicians. He died at Florence, An. 1703, and left 

 many other works, though in an unfinished state. 



In the preface to this book, he gives an account of Aristaeus Senior G^ome- 

 tra, as far as can be gathered from the ancients, and of his writings. This 

 Aristaeus wrote five books of Conic Sections, which Euclid himself valued so 

 much, as to imitate and add to them, as Pappus says. He wrote other five 



* For solutions of this enigmatical problem, see pp. 479 and 609 of vol, iii. of this Abridgment; 

 where also is some account of the life of Viviani. 

 VOL. V. T 



