D O C U M E N T 4 1 8 N O V E M B E R 1 9 2 6 3 9 5 then we have the right to claim that the respective country be categorized among the countries listed under point b). e) If according to point a) a conveyance of the rights by you to third parties occurs, then an income according to point d) must be guaranteed by you, whereby in the event of a one-time payment, 1[2]% of the amount is credited as annual payment. d) You carry all the patent and legal costs. f) All further inventions that we or you make in the area of the respective refrigeration-machine types constitute jointly-owned property and are treated like the other authorized patents. The same applies to improvements and operating ex- perience. 3.) a) In return for the option rights granted to you according to points 1) and 2), you carry all the patent costs also up to the time when the contract comes into force under 2), i.e., until your ev[entual] stated renunciation and thereafter for another half year. In particular, those patents will be registered for which we have a claim before the end of the priority term in the countries......... Furthermore, you pay in return an amount of 3,000– marks. b) Until your decision on the option and for two more months afterward, if we deem it necessary, staff assistants should be made available to us, whose compen- sation you will provide, as needed, up to a total of 750 marks per month. You also bear the total experimentation costs. 418. To Heinrich Zangger [Berlin,] 15 November 1926 Dear Zangger, A dear acquaintance of mine (the psychiatrist Juliusburger) has a daughter just over 20 years of age, the nicest and finest girl you can imagine.[1] She has been di- agnosed with tuberculosis and she must go to Switzerland—if possible to Montana Vermala, as he said. Expert supervision required, of course. These people are in quite modest circumstances. I would like to pay one-third of the costs, without them and my wife[2] knowing about it, especially considering that the girl’s father treated my mother-in-law, who recently died,[3] free of charge. I know that you are informed about relevant circumstances. Please send me an address that seems suit- able to you, including a leaflet with an estimate reduced to 2/3 that I can give to Dr. Juliusburger, without him noticing anything about my ruse. Warm regards and looking forward to seeing you soon, your A. Einstein