Edward Theodore Brewis, Hermann Thoms, Frederick Belding Power, Peter MacEwan and William Lamond Howie. Photograph, 1909.

Brewis was a chemist at the firm of Stafford Allen & Sons. Hermann Friedrich Maria Thoms was a chemist in Berlin. Frederick Belding Power was a chemist with the Wellcome Chemical Research Laboratories and at the University of Wisconsin. Peter MacEwan was the editor of Chemist & druggist. William Lamond Howie FRSE was a pharmaceutical chemist, photographer and mountain climber