5 2 D O C U M E N T S 4 1 , 4 2 S E P T E M B E R 1 9 2 7 41. On German Colonial Policy [Einstein 1927r] Dated 1 September 1927[1] Published December 1927 In: Europäische Gespräche 5, no. 12 (December 1927): 626. Expert opinion seems to be unanimous in asserting that by clearing not yet ara- ble land and making more intensive use of soil surface by dividing up great estates, both the number of people engaged in farming and the overall yield of the land in the territory of the German Empire could be very significantly increased.[2] I con- sider this internal colonization more useful, certain, and congenial than the govern- mental colonization of overseas land foreseen in your inquiry.[3] 42. To Max Barthel[1] [Berlin,] 3 September 1927 Dear Sir, Your remark is quite correct.[2] Indeed, I chose a route similar to that which was suggested by you in my work on Planck’s radiation law, published in the year 1917 however, it was for the case where the process considered consists only of the ab- sorption and emission of radiation, without being accompanied by a dissociation.[3] It must in fact be taken into account that when the influence of the radiation on the recombination process is considered, the method that I followed in 1912 becomes inapplicable, since in that case, the false dynamic equilibrium on which I based my derivations at that time no longer exists. The derivation as suggested by you corre- sponds quite completely to our current understanding of the action of radiation, but it is not new. Respectfully yours,