From R. D. LUCAS
I was intrigued by John Emsley’s article, ‘Molecular footprints in the
sand’ (New Scientist, Science, 4 April) – yet I wondered why Kensaku Morihara
could not obtain pure d-alanine anhydride.
Should it not be possible to use the silica gel to absorb l-anhydride
from a half-and-half mixture, leaving the d form in solution?
R. D. Lucas Theale, Berkshire
