386 EXPERIMENT STATION" EECOED. 



but also that the placenta as well as the serum underwent changes absolutely 

 similar to those we should have expected if we had used, instead, a hemolytic 

 amboceptor and corresponding erythrocytes — namely, the serum was deprived 

 of its property of digesting fresh placenta-protein, and the placenta-protein 

 acquired the property of being digested by any fresh serum. Moreover, such 

 a placenta (sensitized?) could also be digested by serum which was deprived 

 of its specific antibody by exhaustion with placenta in the ice box. . . . 



" To those making routine examinations by the Abderhalden method, it is 

 known that the blood of a patient taken under certain conditions, as when 

 there is high temperature, pus formation, or recent ingestion of a meal, may 

 contain an amount of amino acid sufficient to mask the specific reaction. Whereas 

 the last mentioned factor can be regulated with little inconvenience to the 

 patient, blood being taken before breakfast, it is impossible to obviate the 

 comiilications in the other cases." A modified procedure is presented which 

 will remove some of the errors in the method. 



A note on the preparation of bacterial vaccine, W. J. Stone (Jour. Amer. 

 Med. Assoc, 63 {Idllf), No. 12, pp. 1011, 1012).— When the bacterial growth is 

 removed from the agar, or other medium, there is a tendency to take with it 

 metabolic products and constituents of the medium. These products are apt to 

 cause a relatively severe local reaction. The author recommends washing all 

 bacterial suspensions and separating them with the centrifuge. 



" For purpose of standardization, a suspension of the living, rather than dead, 

 washed organisms is employed. The following method, which is preferable to 

 the blood-cell slide method of Wright because of greater accuracy, was sug- 

 gested some years ago by Dr. L. H. Spooner of Boston, and has been used by 

 me as a routine procedure with satisfaction : A small amount of the suspen- 

 sion is dra^n into an ordinary erythrocyte mixing pipette, diluting 1 : 100 with 

 a fairly deep colored, thoroughly filtered, aqueous carbolthionin stain (the 

 phenol content is 0.5 per cent). The suspension in the counter is well shaken 

 to secure an even distribution of cells and a small drop placed on the shallow 

 blood-platelet counting chamber of Helber-Zeiss. The organisms in 25 small 

 fields are counted and the sum divided by 25 to obtain unit value. The number 

 so obtained is mutiplied by the dilution (1(X)), by 50 (the depth of chamber), 

 by 400 (the number of small squares per cubic millimeter), and lastly by 1,000 

 to convert to cubic centimeters." 



Some further investigations on the detection of anthrax with the pre- 

 cipitation method, Schutz and Pfeileb (Arch. Wiss. u. Prakf. Tierlieilk., 40 

 {1914), ^0. 4-5, pp. 395-424)- — A continuation of the work previously noted 

 (E. S. R., 25, p. 883; 27, pp. 577, 781; 29, p. 378; 30. p. 682), a larger variety 

 of domesticated animals (bovines, horses, sheep, goats, and pigs) and deer be- 

 ing studied. The extracts of the organs were compared by three methods, viz, 

 boiling (physiological salt solution), chloroform, and Ascoli's modified boiling 

 (acetic acid added to the physiological salt solution extract). 



The use of acetic acid as a remover of turbidities in the extract did not seem 

 to have any particular advantage, and after trying other substances, filtration 

 of the extract through dried powdered animal charcoal and filter paper was 

 utilized. Keeping the extract in contact with charcoal for a long time absorbed 

 some of the precipitinogen. In these investigations it was again proved that a 

 chloroform extract of an organ under test gives better results than the ordinary- 

 physiological salt (boiled) extract. The latter gave more negative results than 

 the bacteriological examination. The precipitation test was found reliable for 

 detecting anthrax in bovines horses, and sheep, and may also be used for diag- 

 nosing anthrax in pigs. 



