510 Prof. A. Gamgee. On the Behaviour of Oxy-hcemogldbin, 



A. Magnetic Properties of Acethmmin. 



The acethsemin employed in the present research was prepared by 

 me from ox's blood by the method of SchalfTjew. Some of the speci- 

 mens were purified by recrystallisation from glacial acetic acid, others 

 by dissolving in a chloroformic solution of pure quinine, and subse- 

 quently adding to the filtrate hot glacial acetic acid, saturated with 

 NaCl* 



My first observations were made with a block of agglomerated hsemin 

 crystals weighing 06455 gramme, and measuring 26 mm. in greatest 

 length, 18 mm. in height, and 6 mm. in thickness : this block was 

 suspended by two fibres of silk, so as to occupy the equatorial position 

 in reference to the pole pieces of the magnet. The distance between 

 the poles being 30 mm., on passing a current from three accumulator 

 cells through the coils, the mass instantly assumed the axial position, 

 and was strongly attracted to the nearest pole, the suspending silk 

 fibres being sensibly deflected from their original vertical position. 

 Even when the poles of the electro-magnet were 40 mm. apart, the 

 mass instantly set in an axial position when the current was passed. 

 The observations were repeated with numerous specimens of hsemin, 

 and always with similar results. 



B. Magnetic Properties of Hcematin. 



The hsematin employed in these researches was prepared by dis- 

 solving recrystallised and perfectly pure acethsemin in a weak solution 

 of chemically pure sodium hydrate at ordinary temperatures, and 

 precipitating the filtered solution without delay by neutralising with 

 dilute sulphuric acid. The precipitated hsematin was thoroughly 

 washed, drained, and dried. In consequence of its absolutely amor- 

 phous pulverulent character, my magnetic observations on this body 

 were conducted with the aid of tubes of very feebly magnetic glass, 

 containing from - l to 0"4 of pure hsematin. The intensely magnetic 

 character of hsematin was as easily demonstrated as had been that of 

 acethsenrin. 



8. Preliminary Observations on the Electrolysis of Solutions of Pure Oxy- 

 hemoglobin and CO-hcemoglobin. 



The remarkably definite results of my research, which had shown 

 that Oxy- and CO-hsemoglobin are decidedly diamagnetic substances, 

 whilst their iron-containing derivatives, acethsemin and hsematin, are 



* Refer to my previously quoted article in Schafer's ' Text-book of Physiology,' 

 and to Nencki and Zaleski's recent article " TJntersuchungen iiber den Blutfarbstoff. 

 1. Ueber die Aether des Hamins," ' Zeitschrift fur Physiologische Chemie,' 

 toI. 30, 1900, p. 384, et seq. 



