THE increasing interest that is being taken in natural sources of vitamin C in general, and in the extraction of this vitamin from rose hips in particular, suggests that some observations made by us on the production of a spray-dried rose hip powder may be of interest. In the autumn of 1942 it was desired to prepare a concentrated rose hip extract with high ascorbic acid potency, but a vacuum-evaporated extract proved to be somewhat unstable. In view of our previous success with the spray-drying of apples, plums and black currants, it was decided to apply the earlier technique to rose hips.