 After finishing his studies , ML Pin accompanied Princess <unk> <unk> <unk> on a one @-@ month trip in Europe . Upon return to London , he attended the First World Conference on Adult Education on behalf of Siam , but during the same time his health deteriorated further , and he was diagnosed with tuberculosis . Accordingly , his return trip to Siam had to be postponed in order for him to recover in Switzerland . There he spent almost two years in Davos and later <unk> , until September 1931 when he attended the League of Nations annual conference before returning to Siam via a Nippon Yusen ship departing from Naples , Italy . He finally arrived in Siam on 23 October 1931 , after spending over nine years abroad . 
