i 5 4 SCIENCE PROGRESS. 



If nucleo-proteids and these colloids both produce the 

 same effect in the same way, one is driven to the conclusion 

 that their physiological activity is connected in the first 

 place with the heaviness of their molecules, and in the 

 second with the presence of some radicle common to both. 

 The colloid condition will not entirely explain the action, 

 since many colloids do not act in the same way ; the active 

 radicle is certainly not one which contains phosphorus, since 

 all the colloids are free from that element ; it may possibly 

 be the amido-fatty radicle in a high state of condensation 

 which is responsible for the clotting produced. 



It is these two principal sets of researches that I wished 

 to bring before the readers of "Science Progress," because 

 although both fall short of their ultimate object, the synthesis 

 of proteid, yet they show the way to be followed in the future, 

 and, moreover, they exhibit in themselves certain points of 

 interest, of which the one treated last, the physiological 

 action of Grimaux's colloids, is by no means the least. 



I have not alluded in the foregoing paper to Lilienfeld's work on the 

 synthesis of peptone. He has only brought the matter forward in a 

 preliminary notice, and for important researches of this kind, one requires 

 full details before their value can be estimated. 



BIBLIOGRAPHY. 



(i) Schutzenberger. Compt. Rend., cvi., p. 1407. Ibid., cxii., p. 



198. 



(2) GRIMAUX. Compt. Rend., xciii., 771 ; xcvii., 231, 1336, 1434, 



1485, 1540, 1578. La Revue Scientifique, 18th April, 1886; 

 this gives a summary of the others. 



(3) PICKERING, J. W. Journal of PJiysiology, xiv., 347 ; xviii., 54. 

 Pickering and Halliburton. Journal of PJiysiology, xviii., 



285. 



W. D. Halliburton. 



