... estimation of the amount of hæmoglobin, secondly indirect, such as the determination of the specific gravity or of the volume of the red corpuscles, and perhaps also the estimation of the drysubstance ... such as this is often sufficient to persuade them of the contrary. Of the instruments for measuring the depth of colour of the blood, the double pipette of Hoppe-Seyler is quite the most delicate. ... for the depth of colour of the blood. There are a number of instruments of this kind, of which the "hæmometer" of Fleischl, and amongst others, the "hæmoglobinometer" of Gowers,...