AGGREGATE-APSIDAL. 
76 
Aggregate : and relation in abstract geometry, vi, 459. 
Air: effect on pendulum, iv, 541. 
Airy, Sir G. B. : a trigonometrical theorem, iv, 80; roots in algebraic equations, iv, 116, ix, 39. 
Algebra : non-commutative, I, 128—31, 301 ; notion and boundaries, v, 292—4, 620 ; Cayley founder 
of modern, vili, xxx ; geometrical illustration of theorems in, ix, 16—7, 21—39 ; operation connected 
with covariants, ix, 537—42 ; expansion theorem, x, 57 ; system of equations, xi, 39—40 ; identities, 
xi, 63—4, 130—1; and time, xi, 443; origin, xi, 445—8; in Greece, xi, 446; and logic, xi, 459, 
xii, 459 ; algebraical equations, xi, 506—21 ; function in, xi, 523—4 ; Sylvester’s work, xiii, 46 ; 
Sylvester’s principles of universal, xiii, 47 ; Sylvester on art and, xiii, 48 ; (see also Multiple 
Algebra). 
Algebraic Curves (see Curves). 
Algebraic Equations (see Equations). 
Algebraic Theorems : x, 594, 602, 609. 
Algebras, Non-commutative: i, 128—31, 301. 
Algorithm : for characteristics of triple theta functions, x, 441—5, 452. 
Allink : the term, v, 521. 
Allotrious : the term, ix, 204. 
Alpine Club : Cayley a member, vili, xi. 
Alternant : of operators, xiii, 400—1. 
Altitude : of trees, ix, 429—60. 
America : Cayley’s visit to, vili, xxi. 
American Mathematical Journal: Sylvester's contributions to, xiii, 47. 
Ampère, A. M. : inertia, iv, 563, 584 ; reciprocante, хш, 366. 
Amphigram: the term, vn, 268. 
Ampullate : the term, vi, 101. 
Anallagmatic : the term, vn, 246. 
Analogues: of Pascal’s theorem, i, 426, 427. 
Analysis : Bernoulli’s numbers in, ix, 259—62 ; (see also Combinatory Analysis). 
Analytical Geometry (see Geometry, analytical). 
Analytical Representation of Curves (see Representation). 
Analytical Theorem: as to Euler’s equation, vn, 261—2. 
Analytical Theory of conics (see Conics). 
Anchor Ring: and cyclide, ix, 18. 
Angle : interpreted with reference to two points, vi, 497. 
Anglin, A. H. : roots of algebraic equations, xn, 33—4. 
Angular Distance (see Distance). 
Anharmonic Ratio : theory of binary qualities, n, 565 ; sextic equation, vn, 314—5, xn, 578—9. 
Anomaly : expansion of the true, hi, 139—43 ; and elliptic motion, iv, 521, 523. 
Anti-circle : the term, vili, 262. 
Anti-conic: the term, ix, 65. 
Anti-foci : and foci, vn, 567. 
Anti-point : the term, vi, 499—500, ix, 65, хш, 11 ; problem and solution, vn, 593 ; orthomorphosis 
хш, 184. 
Aoust, L. : geodesic curvature, xi, 330. 
Aplati (see Penultimate Forms). 
Apoclastic: the term, xii, 226. 
Applicable Surfaces (see Skew Surfaces, Surfaces). 
Apollonius: tactions, xiii, 152. 
Apsidal Surfaces : theory of, xi, 111—3.