LUEDEKING — POST-MORTEM DETECTION OF CHLOROFORM. 3I 



Add to the above that chloroform is a powerful preservative 

 agent, I we have a collection of factors sufficient to enable us to 

 understand the lengthy occlusion of chloroform in the animal 

 body, though others of minor importance might be adduced 

 besides these. 



Grehant and Qiiinquaud,§ experimenting on dogs, find the 

 amount of chloroform necessary to produce anaesthesia to be at 

 least one gram to every two litres of blood. On the basis of 

 these results, the total quantity of chloroform in the blood of a 

 man of 150 pounds weight would be 2f grams approximately, 

 when rendered insensible through its inhalation. The amount 

 necessary to produce death would, under normal conditions, cer- 

 tainly not be less than this. Under the assumption that one-sixth 

 of the entire quantity of blood circulating in the body is at all 

 times passing through the lungs, the quantity of chloroform in 

 the lungs of a man of 150 pounds weight, rendered insensible by 

 its inhalation, would be about one-half gram. 



We desire to emphasize by this calculation that there is an 

 abundance of material in the lungs for the detection of chloro- 

 form. The liver would undoubtedly also be very suitable for its 

 detection. 



The Ragsky method is enormously delicate. One part of 

 chloroform in one hundred thousand can still be detected by its 

 means. 



The method of A. W. Hofmann (Ber. Ber. 1871) is less deli- 

 cate, and not available when the quantity of chloroform is less 

 than one part in six thousand. However this is quite sufficient 

 for toxical analytical purposes, and it should always be used as 

 confirmatory of results obtained by the Ragsky method. When 

 the tissues are much decomposed, the distillate obtained at first 

 by means of the current of steam has a very powerful odor, which 

 must be removed by repeated distillation with alcohol at as low 

 temperatures as possible, and preferably under diminished pres- 

 sure. By this means the first distillates will finally be sufficiently 

 deprived of odor to enable successful application of Hofmann's 

 test. Thus also the chloroform, which may have been present 

 in very minute fraction in the original substance, can be concen- 



t Robin and Augendre, C. R., 30, 52; 31, 679. § C. R. 97, 753. 



