Petrolagar : no. 1 blue label (plain) ... no. 2 red label (phenolphthalein) ... no. 3 green label (alkaline) ... / Deshell Laboratories Ltd.
- Date:
- [between 1920 and 1929?]
Licence: In copyright
Credit: Petrolagar : no. 1 blue label (plain) ... no. 2 red label (phenolphthalein) ... no. 3 green label (alkaline) ... / Deshell Laboratories Ltd. Source: Wellcome Collection.
