390 Medico-Legal 



Finally Austin (12. in. '03) in a paper on " the limitations of the 

 Uhlenhuth test for the differentiation of human blood " showed that 

 " other fluids of the human body, like effusions and exudates, were of 

 little value " in the production of antisera. These facts, however, can 

 have no bearing on the test in its medico-legal aspect, and but confirm 

 the observations of others. 



Graham-Smith and Sanger (1903, pp. 269 — 272) at my suggestion 

 examined a number of articles obtained through the courtesy of Mr Henry, 

 Chief of the Criminal Investigation Department of Scotland Yard. The 

 objects in question all possessed forensic interest. They consisted of 

 various weapons and blood-stained fabrics. These authors found that 

 blood which had been dried many years (see also p. 119 et seq.) could 

 still be tested by means of precipitins. I quote the following from 

 their publication which appeared in the Journal of Hygiene. 



A. Blood dried on metal. 



"The results of experiments on 17 samples covering a period of 

 30 years, are arranged according to age in the following table. The 

 number after each specimen refers to the catalogue of the Scotland 

 Yard museum, and a short description of each is given in the appendix. 



The reactions of all were neutral. 



The following table refers entirely to weapons which had been 

 preserved from rusting by the application of oil to the surface of the 

 metal. This process had caked the blood into black masses, making it 

 frequently difficult to say whether the mass consisted of blood and oil 

 or rust and oil. In the majority of cases however it was possible to 

 make certain of scraping off some blood. The material thus obtained 

 was extracted with distilled water, and subsequently an equal volume 

 of l'2 7o salt solution added to it. If necessary the solution was 

 filtered through filter-paper, and tested in the way described. 



Excellent results were obtained from these materials, and showed 

 conclusively that the property of producing a precipitum with its 

 appropriate antiserum is not lost by blood dried on metal even after 

 30 years have elapsed. 



In one case. No. 11, however, no reaction was obtained ; the negative 

 result was probably due to little or no blood being present on that part 

 of the knife which was examined. The condition of the weapon was 

 such that it was impossible to be certain that the material scraped from 

 it was blood, but it was thought better to include it in the series, 



