Page:Eleanor Gamble - The Applicability of Weber's Law to Smell.pdf/58

54 P. Gum ammoniac and gutta-percha, home-made, glycerine soap, oil of mace, coumarine, oil of camphor. Rob. Glycerine soap, gum ammoniac and gutta-percha, home-made, oil of mace, coumarine, vanilline, cedar, gum ammoniac and gutta-percha from Utrecht. Rog. Black rubber, paraffine, coumarine, oil of camphor, caryophyllnine, gum benzoin, oil of anise, laudanum. Se. Tolu, rose-wood, tallow, asafœtida, musk-root, gray rubber, oil of mace, coumarine, musk, ethyl butyrate, citral, caryophylline, allyl suphide. Sh. Black rubber, cedar, gum ammoniac and gutta-percha, from Utrecht, coumarine, oil of camphor. T. Tolu, Russian leather, asafœtida, cedar, coumarine, heliotropine, valerianic acid, citral, pyridin and yellow wax.

The fact that the order was not varied more extensively and more systematically was due to practical difficulties with the apparatus.

V.  $Δr/r$.