1895.] MICROSCOPICAL JOURNAL. 133 



(as thought, though they were only " lung gravel stones") 

 and when I had cough (depending mainly on the irrita- 

 tion of lung gravel,) some emaciation, pallor, and other 

 rational signs of tuberculosis. I insisted that he should 

 tell me as to tuberculosis. He would not and could not. 

 Dr. John A. Lamson of Boston, my medical classmate, 

 Harvard, 1856, also explored my chest with like results 

 of " not proven " and doubtful. But Dr. Salisbury at 

 once showed by the morphology of the blood that the 

 disease was not tuberculosis. The 23 years since lapsed 

 prove this diagnosis true. This is what I have termed 

 the negative diagnosis of tuberculosis. 



POSITIVE DIAGNOSIS OF PRETUBERCULOSIS. 



In a certain number of the aforesaid doubtful cases, 

 the morphology of consumptive blood is found showing 

 that pretuberculosis exists. In pretuberculosis there is 

 and has been a consensus of opinion, medical and lay, 

 that consumption is more tractable and curable (if at all) 

 because there is no detectible lung lesion. I reported 

 such cases to the Berlin International Medical Congress, 

 1890. Some of them date back as far as 1876-7, are liv- 

 ing today, thus more than ten years cured. 



METHODS. 



The process used is a modification of that adopted, intel- 

 ligently described and published by Surg. J. J. Woodward, U. S. 

 A., who is the fether of modern micro-photography and to 

 whom the writer would here express his sincere thanks for ad- 

 vice and encouragement. 



The modification is plight and includes portability. The ap- 

 paratus is packed in a large box ready for use and transported 

 to any point desired. It differs also in the use of only one con- 

 denser instead of two as in Woodward's apparatus. It excludes 

 the blue colored cell of glass or of ammonia sulphate of copper, 

 (1876). It includes the use of objectives the highest in power 

 ever made, namely, the 1-50 and l-75th inch objectives. The 

 highest one he had employed at last accounts, was a l-18th in- 



