VITAMINS HALLIBURTON". 243 



growth factor, and therefore indispensable in early life. It is absent in 

 most vegetable fats. Here we have one indication of the value of milk 

 for the young, an explanation of the potency of cod-liver oil in curing 

 malnutrition, and a warning of the danger of vegetable margarines if 

 employed as the only source of fat in the food of the growing sec- 

 tion of the population or of expectant mothers. It is usual to call this 

 vitamin " Fat Soluble A." There is accumulating evidence to show 

 that its absence or deficiency is an etiological factor in rickets. Like 

 its water-soluble companion, it is ultimately a vegetable product, 

 being contained in high concentration in the green portions of plants. 

 It is because the cow lives on grass that her milk contains the vita- 

 min. In expectant mothers, either milk itself or green vegetables 

 should form important constituents of their diet, but in the feeding of 

 infants green vegetables are for other reasons not suitable, so that in 

 times of stress and shortage children must be provided with milk 

 even if everyone else has to be content with little or none. In the 

 adult the need for " Fat Soluble A " is not so great as in the child, 

 but it has been established that small quantities are necessary, espe- 

 cially in periods where excessive work leads to a greater demand for 

 nutritive principles, for instance, in our fighting forces on active 

 service. 



The third vitamin is also soluble in water, and as Doctor Drum- 

 mond suggests it may be called " Water Soluble C." This is the anti- 

 scorbutic principle, and is found in the juices of fruits (the orange 

 and lemon are here preeminent) and in most edible vegetables. 

 Among a seagoing people like the English, scurvy was but too fa- 

 miliar in the past, and in the sixteenth and seventeenth centuries it 

 was a dread and terrible scourge. The remedy, fresh meat and vege- 

 tables, was well known, but no means existed then for providing 

 ships with these desirable commodities on their slow and protracted 

 voyages. Scurvy also was common among the civilian population, 

 owing no doubt to the scanty allowance of meat and especially of green 

 vegetables available for the poorer classes. Thanks to the increased 

 rapidity of transport and the improved facilities for the provision 

 of fresh vegetables and fruit, adult scurvy has become much less 

 familiar in our days, except in cases of long-continued absence from 

 centers of civilization, such as arise in polar expeditions or under 

 the strenuous conditions of modern warfare. In more recent times 

 the failure of the potato crop in Ireland in 1847 was followed by 

 outbursts of scurvy, as was also the case in Norway in 1904, and the 

 recent failure of the fruit crop in 1917 was marked by outbreaks in 

 Glasgow, Manchester, and Newcastle. In time of war scurvy fre- 

 quently occurs, and numerous instances of this have occurred during 

 the past four years, for example at Kut during the siege. In fact, 

 a considerable proportion of the population are never far removed 



