1899] MICROSCOPICAL JOURNAL. 19 



practitioners and of our patrons. The microscope will be 

 found of great service in the diagnosis and prognosis of 

 disease and a trusty guide to point out indications for 

 treatment. Probably the most frequent use will be the 

 examination of sputa for the tubercle bacilli. This is the 

 quickest and surest method of diagnosis and the best 

 guide as to the progress of a case under treatment. 

 Sometimes the sputa reveal streptococcus infection which 

 is an indication for treatment by an antistreptococcus 

 serum. The same test and treatment has been very suc- 

 cessful in many forms of septicemia. 



The subject of hematology is of itself a vast field for 

 study. It has become an important matter in the diag- 

 nosis and treatment of many diseases and is the only re- 

 liable method of differentiating idiopathic anemias, per- 

 nicious anemia, leucocythemia. and the various forms and 

 degrees of blood impoverishment. The discovery of 

 bacteria and other micro organisms in the blood has 

 prompted more frequent examination and careful study 

 of this vital fluid. Ehrlich's method of staining blood 

 corpuscles has widened our knowledge of the part played 

 by the phagocyte in its warfare against bacterial invasion. 

 Virchow's teaching of the emigration of the white cell 

 in pathological processes and Schultz's observation of 

 the morphological dissimilarity of the white cells in cir- 

 culating blood, are important advances in hematology, 

 which we cannot afford to ignore. So many conditions 

 and diseases are illuminated by a careful study of the 

 blood, that it has become a very important and valuable 

 procedure in medical diagnosis. The Widal test applied 

 to the blood of typhoid fever patients has become a reli- 

 able means of diagnosis and is used by the Board of 

 Health of the city of New York as the official test. 



Before attempting to work with the microscope in clin- 

 ical or other studies, it is essential to future success and 

 good work that one should become thoroughly acquaint- 



