Subject
- Human skin color1
- Indigo1
- Indigo industry1
- Klett Manufacturing Company1
- Klett, Robert E.1
- Laboratories1
- Minneapolis-Honeywell Regulator Company1
- Nylon1
- Optical illusions1
- Packaging1
- Paint1
- Perkin, William Henry, Sir, 1838-19071
- Pharmaceutical chemistry1
- Pharmacists1
- Photovolt Corporation1
- Pigments1
- Porcelain1
- Powders1
- Putnam Dyes1
- S.B. Penick & Company1