VITAMINES 233 



same as those which lead 40 the disease in man. These experi- 

 menters found that guinea-pigs fed exclusively on bread, 

 groats, or unpeeled grain, all died of scurvy within thirty 

 days. Other guinea-pigs who received the same diet with the 

 addition of fresh lemon juice showed no signs of scurvy, 

 although a few of them died of starvation. Another series 

 received only fresh cabbage. No sign of scurvy was detected 

 in these animals, but they all died of starvation because of the 

 lack of nutriment in the food. If, however, the fresh cabbage 

 was strongly heated, or was kept for any considerable length 

 of time, before being given to the guinea-pigs, the guinea-pigs 

 all died of scurvy. These experiments undoubtedly prove that 

 there is some constituent in fresh vegetables which p 4 events 

 scurvy, and, further, that this anti-scorbutic substance or 

 vitamine is easily decomposed by heat or by long keeping. 

 Hoist and Frohlich were inclined to ascribe an enzymatic 

 character to the substance owing to its capacity for producing 

 a large effect although present in such small amount. Other 

 experiments made by these investigators also prove that after 

 the scurvy condition has been produced the giving of fresh 

 vegetable or vegetable juices gradually removes the symptoms, 

 whilst if heated, dried, or long kept, these materials lose their 

 healing properties. 



The exact nature of the anti-scorbutic vitamine or vitamines 

 has not yet been established. The experimental study of scurvy 

 has shown conclusively that they are not necessarily potassium 

 salts, as suggested by Garrod, nor are they effective because of 

 their acid-neutralising properties, as demanded by Sir Almroth 

 Wright's theory of acid intoxication. It would appear at first 

 sight that there must be several different anti-scorbutic vitamines 

 because of the variable stability of the curative principle in 

 different foodstuffs. As a rule, heating the food material — milk, 

 for example — to ioo° C. is sufficient to destroy the anti-scorbutic 

 vitamine contained in it. But lime-juice — one of the most 

 efficient anti-scorbutics — may be heated for an hour at no°C. 

 without affecting its curative power. Preserved vegetables are 

 useless as preventives of scurvy, but lime-juice retains its power 

 for years. It is not impossible, however, that the real agent is 

 identical in each case, the environment being really responsible 

 for the observed differences in the behaviour under the influence 

 of heat and other conditions. The presence of the 7 per cent. 



