Januabt 2, 1920] 



SCIENCE 



17 



teaching and research; for I am first and last 

 a schoolmaster. 



The war having ended more than a year 

 ago, I thought I should like to go to the 

 meeting of the American Association for the 

 Advancement of Science at St. Louis, to meet 

 my colleagues from the other universities and 

 to talk over plans for the future. Now at the 

 last the poor old decrepit TJ. S. Eailroad Ad- 

 ministration, which, I verily believe, has done 

 more than any other single agency to increase 

 the cost of living, decides that this association 

 is not educational ! Therefore, its members 

 are not entitled to the reduced fare previously 

 granted to those attending " meetings of 

 religious, charitable, educational, fraternal, or 

 military character." This, the equivalent of 

 2 cents per mile, which was full fare before 

 the war, may be granted for truly educational 

 gatherings, such as those of public kinder- 

 gartners; but it is not for such as we are: we 

 pay 3 cents per mile with a war tax added, or 

 we help the railroads by staying at home. 



Such is the judgment of a high official in 

 that administration (Mr. Gerrit Fort, assist- 

 ant director), who is doubtless provided with a 

 salary adequate to support him and his family 

 while he renders such decisions. Hear him : 

 " The term ' educational ' taken in its broad 

 sense could be construed to cover a very large 

 number of conventions. It was necessary, 

 therefore, to restrict its definition, and this 

 was done by confining it to those conventions 

 having to do with elementary education, such 

 as meetings of school-teachers." 



This is the last straw! 



Schoolmaster 



SPECIAL ARTICLES 



THE PROTECTIVE INFLUENCE OF BLOOD 

 SERUM ON THE EXPERIMENTAL CELL- 

 FIBRIN TISSUE OF LIMULUS^ 



In the preceding communication we showed 

 that the solutions of difFerent salts, which are 

 constituents of blood serum or seawater, 

 differ in their effect on the cellfibrin tissue 

 and that the amount of regenerative out- 



1 From the Department of Comparative Pathol- 

 ogy, Washington University School of Medicine, 

 St. Louis, Mo. 



growth of the tissue is different in different 

 solutions. If we cover a wound with 6/8 m 

 NaCl healing may take place; a small piece 

 of excised placed on a cover-glass and sur- 

 rounded by a di'op of NaCl solution may show 

 a good outgrowth imder the conditions of our 

 experiment in which usually a small amount 

 of blood serum was adherent to the piece. 

 However, all of these solutions are inferior to 

 the blood serum of Limulus. It was of inter- 

 est to determine which constituent or combi- 

 nation of substances in the blood serum was 

 responsible for the superiority of the serum, 

 whether it was caused by the balancing action 

 of salts or by another constituent. 



Addition of calcium chloride in various 

 quantities to the sodium chloride solution did 

 not improve the latter and usually made it 

 less favorable for the tissue. The addition of 

 seawater in which the inorganic constituents 

 are present in proportions similar to thosa 

 found in blood serum, prevented an active 

 outgrowth altogether. Inasmuch as it was 

 possible that the alkalinity of the seawater 

 was injurious to the tissue, we used seawater 

 with a hydrogen ion concentration which cor- 

 responded to an approximately neutral solu- 

 tion. This did not improve the effect of sea- 

 water. The Van't Hoff solution mixture of 

 salts was likewise much inferior to an isotonic 

 l^aCl solution. These results made it im- 

 probable that the beneficial effect of blood 

 serum was due to inorganic constituents. 



This conclusion was corroborated by the 

 effect of the heating of blood serum. Heat- 

 ing the blood serum to 85° for a short time 

 sufficient to coagulate a certain amount of 

 its proteid destroyed the greater part of tho 

 beneficial effect of blood serum. Heating 

 this filtered fraction still further to 100° for 

 a short time, and thus producing an addi- 

 tional coagulation, made the blood serum as 

 unfavorable as seawater; such heated and 

 filtered blood serum had still the blue color of 

 normal oxygenated Limulus blood. However, 

 how far a proportionality exists between the 

 intensity of heating and of loss of beneficial 

 properties of the serum needs further investi- 

 gation. 



