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b. Preservation with Formaldehyde, by which forma- 

 line-tablets, wrapped in paper, were placed amongst 

 the rice. 



Although this proved to be useless and even injurious, 

 just as the CaO, this could at any rate be spoken of as a 

 preservative, for insects and other parasites were completely 

 prevented. After having been stored for longer than half 

 a year, there were no signs of breakage or brittleness and 

 it even seemed that the grain was hardened. The original 

 colour of the rice was better retained in the long run than 

 when alcohol or even chloroform and CC1 4 was used. 



In contrast with these advantages was the disadvan- 

 tage that formaline, even in the short space of one day, 

 had a most unfavourable influence on smell and taste; 

 this was less noticeable with the unboiled rice than during 

 the steaming process. The disagreeable, pungent smell of 

 formaldehyde could easily be distinguished in the boiled 

 rice, while the taste was modified in the same manner, 

 though in lesser degree. 



A still greater objection to the use of formaline as a 

 preservative is not so much that it reduces the curative 

 effect of the silver-skin, but that it communicates in a high 

 degree poisonous properties to the grain, which will be shown 

 below by experiments taken on rice-birds. This fact was 

 clearly shown after the rice had been kept for 2'/ 2 weeks 

 with formaline. When fed with such rice, these test-animals 

 generally died in about 7 days. When rice was used which 

 had been preserved with formaline during four months, death 

 generally followed in 2 days' time. 



c. Preservation ivtih Snlpliiirons-acid (S0 2 ). 



A great advantage of S0 2 as preservative is that it has 

 at the same time a bleaching effect, so that it imparts to 

 the grain, also that of unpolished rice, a cleaner and whiter 

 appearance. 



Even after having been preserved with S0 2 for half a 

 year, there was little or no sign of breakage or brittleness to 



