Copy letter from Herbert Rix, to Monsieur le Dr Gedoeldt, Directeur de "La Cellule", Rue du Canel, 20, Louvain 'Dear Sir, We have obtained by purchase the earlier volumes of "La Cellule", and the exchange will therefore commence only with the present year. Do you prefer to have the "Philosophical Transactions" ['Philosophical Transactions of the Royal Society'] in separate papers as published, or in annual volumes. I am, yours truly, H Rix Asst. Sec. R.S. [Assistant Secretary, Royal Society]'. 20 July 1893