 Now further disagreements developed; Burton maintained that they had promised each other in Aden not to make public announcements till they both were back in England and Burton accused Speke of a breach of promise by publicly claiming the source of the Nile was found on their trip.Burton now turned against the theory that Lake Victoria was the source of the Nile (and now said the river flowing "out" of the north side of Lake Tanganyika was the source) and thus also reversing himself from the position he took in the letter to Norton Shaw.In that same letter to Shaw, Burton had also stated that Speke would present his findings to the RGS as he was prevented from traveling as he was in poor health and would be in England a short time after Speke.