BY DR. BURDOX-SANDERSON. 179 



be rendered white by washing. In a the fibrin has passed 

 through a previous condition in which it was gelatinous. In 

 b it is obtained directly in the fibrillated state. 



4. Some plasma is diluted with one hundred times its 

 volume of ice-cold water, or three-quarter per cent, salt solu- 

 tion, and allowed to stand. After twenty-four hours, it will 

 be found that there are long delicate filaments of fibrin, which 

 stretch across the mass of liquid in every direction, from one 

 side to the other of the vessel in which it is contained. These 

 filaments, the extremities of which adhere to the glass surface, 

 are in the highest degree elastic. If they are separated from 

 their points of attachment, they shrivel up into little lumps of 

 fibrin. If these again be drawn out into lengths, they resume 

 their original form when let go, as completely as a bit of 

 India-rubber would do. 



5. The fibrin prepared in 3 is placed in water containing one 

 per thousand of hj'drochloric acid. At first it swells out into 

 a bulky l^aline mass. If it is then placed in the air bath, 

 and kept at a temperature of from 40 to 60 C., it wastes 

 away at a rate which varies according to the temperature. 

 In undergoing solution the fibrin has been transformed into 

 another albuminous compound, syntonin or acid-albumin. 1 

 If the liquid is carefully neutralized, the syntonin is precipi- 

 tated, but the precipitate is redissolved in a slight excess of 

 alkali or alkaline carbonate. 



6. Another portion of the same fibrin is soaked in solution 

 of peroxide of hydrogen. It is then placed on a sheet of fil- 

 tering paper, which has been previously soaked in tincture of 

 guaiacum. It soon becomes surrounded with a border of blue, 

 in consequence of the oxidation of the guaiacum. Another 

 method consists in first steeping a fragment of fibrin in alco- 

 hol, then in tincture of guaiacum, and finally immersing it in 

 the solution of the peroxide : the fibrin becomes blue. The 

 same thing happens if the fibrin is dipped in a mixture of the 

 tincture and the solution. This reaction signifies simply that 

 fibrin decomposes peroxide of hydrogen: it affords no proof 

 of the presence of ozone. 



4. Experiments relating to the so-called Fibrin 

 Factors Paraglebulin and Fibrinogen. In every act 

 of coagulation, fibrin appears to be produced by the combina- 

 tion of two albuminous substances closely allied as regards 

 their chemical characters, both of which are to be found in 

 plasma as obtained by any of the methods above described. 

 Fifty cubic centimetres or thereabouts of the plasma, which 

 has been kept at a freezing temperature, are added, in a beaker, 



1 The ending in is adopted here and elsewhere to denote that the 

 word is used in a stoechiological sense. Albumen is white'of egg. 



