and Laboratory Methods. 1671 



4. Float the section on the slide and arrange it smoothly, removing super- 

 fluous water. 



5. Cover the section with a sheet of smooth cigarette-paper, and then press 

 on this, over the section, a pad of soft, smooth filter-paper, the surface of 

 which has been moistened with ninety-five per cent, alcohol. On removing the 

 pad of filter-paper, the cigarette-paper, which remains in contact with the slide 

 and the section, is carefully stripped off, leaving the section adhering to the 

 slide. The cigarette-paper prevents the fibers of the filter-paper from adhering 

 to the section and marring its appearance. 



6. Cover the section sticking to the slide with absolute alcohol for about 

 thirty seconds and drain. 



7. Flow over the section and the adjacent surface of the slide a very thin 

 solution of celloidin in equal parts of absolute alcohol and ether. Drain ofif 

 immediately. The celloidin should form a coating so thin as to be invisible. 



8. Flood the slide with ninety-five per cent, alcohol, and then at once immerse 

 it in water for ten seconds. This hardens the thin film of celloidin and prevents 

 the section from curling and leaving the slide during the subsequent manipula- 

 tions. 



9. Stain with haematoxylin, or any other stain or combination of stains. The 

 methods of staining tubercle bacilli in paraffin sections are applicable to sections 

 obtained by this method. 



10. Dehydrate in ninety-five per cent, alcohol followed by a little absolute 

 alcohol. Unless care is exercised, the absolute alcohol will cause loosening of 

 the section by dissolving the celloidin. 



11. Clear with oil of origanum. 



12. Mount in Canada balsam. 



This method has a wide field of application. It is especially serviceable in 

 making microscopical diagnoses of surgical material during operations. Fasten- 

 ing the section smoothly to the slide not only prevents distortion of the section 

 by dehydrating and clearing agents, but it facilitates the various manipulations 

 and it saves time. By this method good smooth sections, stained, cleared, and 

 mounted in balsam, may be obtained within a few minutes after the specimen is 

 received. 



The fixation of the material before the cutting of the section is essential. If it 

 is not done the section will adhere to the cigarette-paper in the process of press- 

 ing it on the slide. Alcohol or Zenker's fluid may be used instead of formalin. 

 In either case, however, the specimen must be thoroughly washed in water to 

 remove the fixative before it can be frozen, j. h. p. 



Williams, H. U. The Frequency of Trichinosis I" the pathological department of the 

 in the United States. Journal of Medical University of Buffalo, samples of mus- 

 Research, 1: 64, 1901. ^j^^ secured at 505 unselected autop- 



sies on adult human subjects were examined microscopically for trichinellae (trich- 

 inae). They were found in twenty-seven cases, or 5.3 per cent. 



Of the muscles examined the diaphragm was most frequently and most exten- 

 sively affected. When it was not possible to examine fresh specimens the muscle 

 was preserved in a weak solution of formaldehyde. This served its purpose 

 well, as the worms appeared very distinct ; but the muscle was rendered tough 

 and somewhat difficult to compress. The lesions varied greatly in extent. The 

 infection was sometimes so slight that only one or two worms were discovered. 

 Eosinophiles were not found in the vicinity of the encapsuled trichinellse. 

 Plasma cells occasionally appeared in or about the capsules, and sometimes there 

 was a new formation of elastic fibers. J- h. p. 



