THE PRACTICAL OUTCOME OF SCIENCE. 485 



method of distinction, which, consists in breaking up the corpus- 

 cles. By means of a little acetic or sulphuric acid this may be ac- 

 complished, and then on slowly evaporating the solution we get 

 crystals characteristic of the animal to which the blood belonged. 

 By combining these two methods blood can be identified, not with 

 absolute certainty, but with a high degree of probability. 



However, probability is not enough. In a question where a 

 man's life is at stake something more is demanded. Not proba- 

 bility merely but absolute certainty alone can satisfy the people. 

 This in many cases we have. In 1852, in Essex, England, a man 

 was tried for the murder of a woman. She had been found dead 

 in her bed, with her throat cut from ear to ear. Among the pris- 

 oner's possessions was found a razor clotted with blood, and in the 

 blood were detected two or three short cotton fibers. Taken and 

 examined microscopically and compared with the clothing of the 

 woman, it was found that in cutting her throat the assassin had 

 cut through the strings of her night-cap, and these minute fibers 

 of that remained as the silent witnesses of his guilt. 



Sometimes mud or dirt adherent to clothes connects a person 

 with crime, or a hair sticking under the nail of a boot may by 

 comparison show that its possessor has trampled upon the head of 

 the deceased ; or, as in a case at Hull, England, the Diatomacecz 

 adhering to a man's shoes proved that he had been at the place 

 where the murder had been committed. 



Such are some of the ways in which the microscope aids us in 

 ferreting out the assassin. It has, however, a wider application. 

 Some years ago Ehrenberg, that old prince of microscopists, was 

 employed by the Prussian Government to investigate a case of 

 smuggling. A cask had been opened, valuables extracted, and the 

 cask repacked, and shipped onward to its destination. The only 

 clew to the criminals was that the unpacking must have been 

 done at some of the custom-houses through which the goods 

 passed. To all appearance, the microscope had a hopeless task. 

 But not so. Ehrenberg took some of the sand that had been used 

 in the repacking, placed it under his microscope, looked through 

 his magic tube, and behold, there on the stand lay a peculiar speci- 

 men of Foraminifera That animal was found at only one place 

 in the known world, and told at just what point the crime had 

 been committed. 



The history of England furnishes another illustration of the 

 use of the microscope as a detecter of crime. A few years since 

 the people were very much troubled about adulterations. Not 

 only the tea and coffee they drank, but the food they ate, their 

 medicines, and even their clothing were mixed up with foreign 

 ingredients. In some cases this was carried to such an extent as 

 to be simply diabolical. Wisely and well did the Government act. 



