4G0 



SCIENCE. 



[N. S. Vol. XIX. No. 481. 



■wliich lie became much heated, with intervals 

 •of leisure and exposure to cold drafts of air. 

 The immediate reasons for his admission were 

 ■a chill and inability to continue work. There 

 "was nothing unusual in the clinical course of 

 i:he pneumonia or peculiar in his treatment. 

 -A few days after he entered the hospital 400 

 >c.c. of a clear serous fluid was aspirated from 

 the affected side of the chest and was exam- 

 ined on the same day, with the following re- 

 sults : 



Distinctly alkaline, specific gravity, 1021 ; 

 depression of freezing point, 1.383° C. (mean 

 of three examinations with different portions 

 of the fluid, 1.395, 1.385 and 1.370° C. respect- 

 ively) ; electrical conductivity, 0.009119 ; chlo- 

 rine calculated as NaCl, 0.58 per cent. ; total 

 nitrogen, 0.84 per cent. ; nitrogen from washed 

 tannic acid precipitate expressed in percentage 

 of the fluid, 0.83 per cent.; proteid (N X 6.25), 

 5.21 per cent, of the fluid; traces of reducing 

 substance (sugar?) after removing proteids 

 with ferric acetate ; traces of nitrogen liber- 

 ated by hypobromite of soda; no extractives 

 of appreciable amount upon shaking with 

 ether, acetic ether, or chloroform. 



The matter of chief interest in the results 

 was the considerable depression of the freezing 

 point — 0.81° 0. greater than that by the blood, 

 which was found to be 0.57° C. This 0.81° C. 

 represents nearly 0.438 gram-molecule in solu- 

 tion in excess of the molecular concentration 

 of the blood, and appears to be a clear indica- 

 tion that osmotic interchanges between this 

 fluid and the blood did not freely take place, 

 possibly because of a thick layer of fibrin upon 

 the pleural surfaces. Such a deposit would 

 not, however, explain the high molecular con- 

 centration of the fluid. It appears most prob- 

 able that this was produced subsequent to the 

 formation of the fluid, by cleavages in the 

 larger molecules originally present in solution 

 or by the solution of substances not at first 

 dissolved. These substances could not be dis- 

 sociable, because the electrical conductivity 

 was rather lower than is usual in such fluids. 

 If the substances causing the high molecular 

 concentration were organic compounds they 

 were not extractives soluble in ether, acetic 

 ether or chloroform. 



On the assumption that cleavage products 

 of proteid substances, precipitable with tannic 

 acid, might be present and cause the unusual 

 depression of the freezing point, the following 

 experiments were made: Sterile horse serum, 

 which had not been subjected to heat, was 

 divided into portions. Of these some were 

 kept for controls and others were inoculated 

 with pure cultures of Staphylococcus pyogenes 

 aureus, or Fraenkel's pneiunococcus. Freezing- 

 point determinations were made on certain of 

 these portions and the rest were sealed up in 

 pipettes holding 100 c.c. each. These were 

 incubated at 37° C. for a week, when freezing- 

 point determinations were made on one of the 

 controls and one of the tubes inoculated with 

 each of the bacteria mentioned. Cultures at 

 this time showed the presence of great num- 

 bers of the species used, with no admixture 

 of other species. The remaining tubes were 

 left in the incubator for several months, when 

 cultures proved to be sterile. The results of 

 physico-chemical examination of these sera are 

 tabulated below: 



HOESE SERUM A. 



sterile Controls. 



1903 ■ °C. 



May 19— A =0.580; K=r0.009394 

 May 20— A =0.580; K = 0.009491 



1904 

 Jan. 16— A = 0.590 ; K = 0.009684 



Inoculated with Staphylococcus. 



1903 °C. 



May 19— A =0.585; K = 0.009370 

 May 26— A=0..5S5; K = 0.009674 



1904 

 Jan. 16— A =0.640; K = 0.010128 



nOESE SEEUM B. 



Sterile Controls. 



1903 °C. 



May 21— A =0.560; K = 0.009516 

 May 28— A =0.560; K = 0.009516 



1904 

 Jan. 15— A =0.600; K = 0.009S97 



Inoculated with Staphylococcus. 



1903 "C. 



May 28— A = 0.580 



1904 

 Jan. 15— A = 0.640; Iv = 0.010372 



