Almagest, a. [170].

Almanac, a. [181].

Alphonsine tables, a. [178].

Alternation (of formations), b. [538].

Amphoteric silicides, b. [352].

Analogy (in Natural History), b. [418].

Analysis (chemical), b. [262].

Analysis (polar, of light), b. [80].

Angle of cleavage, b. [322].

Angle of incidence, b. [53].