INDEX. 



ABACUS, logical, 104 ; arithmetical, 

 107 ; Panchrestus, 182. 



Aberration of light, 561 ; syste- 

 matic, 547. 



Abscissio infiuiti, 79, 713. 



Abstract terms, 27 ; number, 159. 



Abstraction, 704 ; logical, 25 ; nu- 

 merical, 158 ; of indifferent cir- 

 cumstances, 97. 



Accademia del Cimento, 427, 432, 

 436, 527. 



Accident, logical, 700. 



Accidental discovery, 529. 



Achromatic lenses, 432. 



Actinometer, 337. 



Adamantine medium, 605, 751. 



Adjectives, 14, 30, 81, 35; inde- 

 terminate, 41. 



Adrain, of New Brunswick, 375. 



Affirmation, 44. 



Agassiz, on genera, 726 ; on crea- 

 tion of species, 763. 



Agreement, 44. 



'iry, Sir George Biddell, on per- 

 petual motion, 223 ; new property 

 of sphere, 232 ; pendulum experi- 

 ments, 291, 30-1, 348, 567 ; stan- 

 dard clock, 353 ; book on Errors 

 of Observation, 395 ; tides, 488 ; 

 extrapolation, 495 ; Thales' 

 eclipse, 537 ; interference of 

 light, 539 ; density of earth, 291. 



Alchemists, 505 ; how misled, 428. 



Algebra, 123, 155, 164; Diophan- 

 tine, 631. 



Algebraic, equations, 123 ; geo- 

 metry, 633. 



Allotropic state, 663, 670. 



Alloys, possible number, 191 ; pro- 

 perties, 528. 



Alphabet, the Logical, 93, 104, 125 ; 

 Morse, 193. 



Alphabet, permutations of letters of 

 the, 174, 179. 



Alphabetic indexes, 714. 



Alternative relations, 67 ; exclusive 

 and unexclusive, 205. 



Ampere, electricity, 547 ; classifi- 

 cation, 679. 



Anagrams, 128. 



Analogy, 627 ; of logical and nume- 

 rical terms, 160 ; and generali- 

 sation, 596 ; in mathematical 

 sciences, 631 ; in theory of undu- 

 lations, 635 ; in astronomy, 638 ; 

 failure of, 641. 



Analysis, logical, 122. 



Andrews, Prof. Thomas, experiments 

 on gaseous state, 71, 613, 665, 

 753. 



Angstrom, on spectrum, 42*. 



Angular magnitude, 305, 306, 326. 



Antecedent defined, 225. 



Anticipation of Nature, 509. 



Anticipations, of Principle of Sub- 

 stitution, 21 ; of electric tele- 

 graph, 671. 



Apparent, equality, 275; sequence 

 of events, 409. 



Approximation, theory of, 456 ; ti 

 exact laws, 462; mathematical 

 principles of, 471 ; arithmetic of, 

 481. 



Aqueous vapour, 50. 



Aquinas, on disjunctive propor- 

 tions, 69. 



3 D 2 



