TLM-P struck up a friendship with the Prussian explorer,Ludwig Leichhardt. Leichhardt, 'a brilliant intellectual and man of science'¹⁾ was six years older than TLM-P, and arrived in Sydney three years after TLM-P, in 1842. In September that year Leichhardt visited Dalwood where TLM-P was working, and in June 1843 the two travelled to Moreton Bay.²⁾

In September 1843, TLM-P wrote to Leichhardt from Limestone Station at Ipswich.³⁾ The legible parts of the letter reveal that the two men were both, as TLM-P wrote, great travellers. TLM-P had been in Sydney the previous week and was now 'on the Logan River' and planning to sell his current property to go into partnership in another property with a friend Aikman. TLM-P referred to travelling with Leichhardt, asking him if he 'would like again to be “Compagnons de voyage”'[travelling companion]. Leichhardt had a divisive personality, with people tending to either warmly admire or, equally warmly, dislike him.⁴⁾ He was firmly allied with the squatters, as they could sponsor him when he explored the country in return for information about desirable country to settle.⁵⁾ TLM-P was typical of the squatter admiration for Leichhardt, calling Leichhardt in his letter his 'chere amie' (dear friend) and sending news of mutual friends, including Anne,'a very nice girl'. Perhaps it helped that TLM-P could converse easily in French, though there is no indication that he knew Leichhardt's mother tongue. In 1846, TLM-P promised £2 towards a public testimonial to 'Dr. Leichhardt and his party', to help finance their latest exploring expedition.⁶⁾

There is a mention of 'Mr Ludwig Leichhardt' in the Rosewood station accounts, showing that TLM-P sold a chestnut filly to him for £23.⁷⁾ Note the careful social distinctions of the day - Leichhardt was 'Mr' not 'Esq' because he did not own land (at least not in Australia) so was not a member of the landed gentry entitled to the honorific Esquire.