OXYHEMOGLOBIN IN DILUTE SOLUTIONS 147 



is approximately 3-8. The temperature coefficient of the equihbrium 

 constant may therefore be expected to be somewhere about the 

 latter figure. 



Variation of concentration of reacting substances. The effect of con- 

 centration, as such, has yet to be studied. Hartridge and Roughton 

 had very little choice in the concentration of haemoglobin and of 

 oxygen which they used; they were tied to the only one which 

 would give their measurements. 



The kinetics of oxyhsemoglobin only form one portion of Hartridge 

 and Roughton's work : carboxyhgemoglobin has been studied as well 

 and is discussed in Chapter xv. 



Moreover, the spectroscope is not the only method by which they 

 have observed the progress of reactions in their observation tubes. 

 Thermal (5) methods have also been used with success, and these 

 methods are of importance because they render the whole technique 

 available for the exploration of many rapid reactions taking place 

 between colourless reagents. 



REFERENCES 



(1) Hartridge and Roughton. Proc. Roy. Soc. A. cvn. 643. 1925. 



(2) Barcroft and Hill. Journ. Physiol, xxxix. 411. 1910. 



(3) OiNUMA. Journ. Physiol, xlhi. 364. 1911. 



(4) Hartridge and Roughton. Proc. Roy. Soc. A. en. 595. 1923; civ. 376. 1923; 



civ. 395. 1923; cvn. 654. 1925. Ibid. B. xciv. 336. 1923. 



(5) Hartridge and Roughton. Proc. Camb. Phil. Soc. xxn. 429. 1924. 



