- Artists--Great Britain1
- Artists--New Mexico--Taos1
- Artists--United States1
- Aspirator1
- Astronomy1
- Atomizer2
- Auctions1
- Auditoriums2
- Authors4
- Authors, American--20th century1
- Authors, English--18th century--Portraits1
- Autopsy3
- Awards1
- Bacteriologists4
- Bacteriology1
- Benefactors1
- Binoculars1
- Biochemists17
- Biologists5
- Biostatistics2