Wallace was great friends with Theodore Dru Alison Cockerell, an American zoologist who, in 1912, was professor of systematic zoology and a lecturer at the University of Colorado, USA. Cockerell’s students sent Wallace a letter of appreciation and greeting’s card for his 89th birthday in January 1912 which was signed by 129 students. They wrote at the top the letter:
"To Dr. Alfred Russel Wallace:
We, the students in the General Biology Class at the University of Colorado, ardent admirers of your work on Evolution, send you respectful greetings on the occasion of your eighty-ninth birthday, wishing you health and happiness."
Above: Letter to Wallace from Biology students at Colorado University. © Natural History Museum, London
Wallace wrote a reply to the students, enclosing it in a letter to Cockerell. He wrote to his friend that he was writing in response "to the very kind greetings of the members of your class of general Biology" and that they can have "no more capable and enthusiastic teacher".
In his letter to Cockerell’s students, dated 12 January 1912, Wallace gives a fascinating insight into his feelings of nature that he describes as the "solace of my life". He goes on to write "my first views of the grand forests of the Amazon; thence to the Malay Archipelago, where every fresh island with its marvellous novelties and beauties was an additional delight – nature has afforded me an ever increasing rapture". Wallace describes how his love of nature has not dwindled over the years but has in fact been cultivated in a different way through his "wild garden and greenhouse". Wallace’s letter to the Biology students is very touching and insightful and the students were extremely privileged indeed to receive such a letter.