CARBON-MONOXIDE HAEMOGLOBIN. 279 



part of the spectrum. The middle of the first band corresponds to 

 /I =570, and the second to A =542 (LEWIN, MIETHE and STENGER). 

 These bands do not change noticeably on the addition of reducing 

 substances; this constitutes an important difference between carbon- 

 monoxide hemoglobin and oxyhsemoglobin. If the blood contains oxy- 

 haemoglobin and carbon-monoxide hemoglobin at the same time, we 

 obtain on the addition of a reducing substance (ammoniacal ferro-tartrate 

 solution) a mixed spectrum originating from the hemoglobin and carbon- 

 monoxide hemoglobin. Carbon-monoxide hemoglobin also gives a band 

 in the violet /l = 416. 



A great many reactions have been suggested for the detection of car- 

 bon-monoxide hemoglobin in medico-legal cases. A simple and at the 

 same time a good one is HOPPE-SEYLER'S alkali test. The blood is treated 

 with double its volume of caustic-soda solution of 1.3 sp. gr., by which 

 ordinary blood is converted into a dingy brownish mass, which when 

 spread out on porcelain is brown with a shade of green. Carbon-monoxide 

 blood gives under the same conditions a red mass, which if spread out 

 on porcelain shows a beautiful red color. Several modifications of this 

 test have been proposed. Another very good reagent is tannic acid, 

 which gives with dilute normal blood a brownish-green precipitate and 

 with carbon-monoxide blood a pale crimson-red precipitate. 1 



As according to BOHR there are several oxyhaemoglobins, so also, according 

 to BOHR and BocK, 2 there are several carbon-monoxide haemoglobins, with 

 different amounts of carbon monoxide. As haemoglobin can unite with oxygen 

 and carbon dioxide simultaneously, as shown by BOHR and TROUP, so also can it 

 unite with carbon monoxide and carbon dioxide simultaneously and independently 

 of each other. 



Carbon-monoxide methaemoglobin has been prepared by WEIL and v. ANREP 

 by the action of potassium permanganate on carbon-monoxide haemoglobin, 

 but this is contradicted by BERTIN-SANS and MoiTESSiER. 3 Sulphur methaemo- 

 globin is the name given by HOPPE-SEYLER to that coloring-matter which is 

 formed by the action of sulphuretted hydrogen upon oxyhaemoglobin and which 

 is generally designated sulphcemoglobin. The solution has a greenish-red, dirty 

 color, and shows two absorption-bands between C and D. This coloring-matter 

 is claimed to be the greenish color seen on the surface of putrefying flesh. 

 According to HARNACK the conditions are different when H 2 S is passed through 

 an oxygen-free solution of haemoglobin (or carbon-monoxide haemoglobin). The 

 sulphsemoglobin thus formed shows one band in the red between C and D. 

 According to CLARKE and HURTLEY 4 the formation of sulphaemoglobin takes 

 place after the reduction to haemoglobin. 



1 In regard to this test (as suggested by Kunkel) and others we refer to Kostin, 

 Pfliiger's Arch., 84, which contains a very excellent summary of the literature on the 

 subject. See also de Domenicis, Chem. Centralbl., 1908, 2, p. 66. 



2 Centralbl. f . Physiol., 8, and Maly's Jahresber., 25. 



3 v. Anrep, Arch, f . (Anat. u.) Physiol., 1880; Sans and Moitessier, Compt. rend., 113. 



4 Hoppe-Seyler, Med.-chem. Untersuch., 151. See Araki, Zeitschr. f. physiol. Chem., 

 14; Harnack, 1. c.; Clarke and Hurtley, Journ. of Physiol., 36. 



