Improvements in means of determining the proportion of haemoglobin in blood / [Theodor Waldemar Tallqvist].

  • Tallqvist, Theodor Waldemar.
Date:
1903
Catalogue details

Licence: Public Domain Mark

Credit: Improvements in means of determining the proportion of haemoglobin in blood / [Theodor Waldemar Tallqvist]. Source: Wellcome Collection.

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    Date of Application, 9th Oct, 1902—Accepted, 1st Jan,, 1903 COMPLETE SPECIFICATION. “ Improvements in Means for Determining the Proportion of Haemoglobin in Blood.” I, Theodor Waldemar Tallqvist, of No. 1 Parkgatan, in the Town of Borga, in the Grand Duchy of Finland, Russia, Doctor of Medicine and Surgeon, do hereby declare the nature of this invention and in what manner the same is to be performed, to be particularly described and ascertained in and by the h following statement ; — It is well known that the ascertaining or measuring of the quantity of haemoglobin contained in the blood forms an important means for judging the state of disease in anaemic patients. There are already in existence various kinds of apparatus for this purpose, most of which are based upon the same 10 principle as my said invention.—namely, on the colourimetric measurement of the quantity of haemoglobin. All these give more or less exact and reliable results; but they all have one disadvantage in common—namely, that an ex¬ animation of the blood with their assistance can be done only under certain conditions and that such an examination requires time and is inconvenient. It 15 must therefore prove a considerable boon to the medical practitioner if the cumbersome work with such an apparatus (hemometer) could be replaced by one single and easy observation, which can be made immediately when the patient is being examined and independently of a dark room, a special source of light, or other special circumstances. -^1 My investigations in this direction were preceded by somewhat extensive examinations of the natural colour of the human blood at various degrees of diseased changes in the same. In order to obtain uniform results in judging the colour of the blood I used white filtering-paper, which was neared to the drop of blood in such a manner as to make it suck the blood slowly till the 25 paper was thoroughly drenched by it. The colour was then observed as soon as the blood-stain had lost its humid gloss, the stain being pressed against a pad of the same filtering-paper and the observation always being made by direct light. The blood, however, changes in colour very quickly, owing to the action of the air, and it therefore became necessary to make artificial 30 copies of the blood-stains before the changes in colour had begun. By making a complete series of observations and artificial copies of the respective colours and by checking these through repeated observations I have determined that the colour of the blood-stain on the filtering-paper from different patients and with different kinds of blood diseases always corresponds with the same per- 35 centage of haemoglobin in the blood. My invention relates to a scale of colours which I have composed on the basis of the researches described heretofore in such a manner that each shade of colour in this scale corresponds to a certain stated quantity of haemoglobin contained in the blood. 40 The ascertaining of the quantity of haemoglobin by the aid of my scale is performed in the following manner: A sample of the blood under examination is taken on white filtering-paper of suitable quality in the manner described above, and this sample is compared with the said scale. The figure standing opposite that shade of colour which corresponds the nearest with the colour 45 of the said sample gives the percentage of haemoglobin in the blood under examination. It is evident that an examination of the quantity of haemoglobin by the [Price §d,J