Acumination, b. [319].

Acute harmonics, b. [37].

Ætiology, b. [499].

Affinity (in Chemistry), b. [265].

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

Agitation, Centre of, a. [357].

Alidad, a. [181].

Alineations, a. [158], [161].

Alkali, b. [262].

Almacantars, a. [181].