THE MICROSCOPE AS DETECTIVE 



scrupulous to sell " raspberry " jam contaminated 

 with a large percentage of some cheaper fruit, such 

 as gooseberry. The seeds of the two fruits differ so 

 markedly that it is really not necessary to employ 

 a microscope to discover the fraud, but a case is on 

 record where wooden seeds were used, so like the 

 true seeds of the raspberry, that a very careful 

 examination was necessary to show what had hap- 

 pened. In our chapter on the Microscope in Agri- 

 culture we have referred to this point in greater 

 detail. Starch of various kinds is a very common 

 food adulterant and the experienced microscopist 

 can estimate almost precisely, the proportions of 

 different starches in a mixture, a feat which would 

 sorely puzzle the chemist. So in certain cases the 

 microscope is indispensable. 



Briefly the microscope is a time saver; chemical 

 tests occupy a considerable time; microscopic ex- 

 amination is quick, the experienced microscopist at 

 once recognises what he observes. Very small 

 quantities can be examined under the microscope, 

 relatively large quantities are required for chemical 

 tests. Again, if only a small quantity of the 

 material is available for examination and it is neces- 

 sary to carry out chemical tests, they can be per- 

 formed under the microscope and this point is 

 considered in another chapter. 



We have mentioned that starch of various kinds 

 is a common adulterant of many foods and the 

 bildding food analyst might do worse than learn 

 to recognise the various starch grains under the 



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