N'afọ 1915, Davidson na ụmụ akwụkwọ ndị ọzọ dị iri atọ so ya kwọ ụgbọala Cadillac asatọ a rụgharịrị arụgharị si na Chicago gaa San Fransisko
ma laghachi n'etiti nnukwu mkpọtụ nke ndị nta akụkọ nọ n'ụzọ. Ụgbọala ahụ malitere n'akụkụ ụlọ akwụkwọ Highland Park ebe Davidson nọ n'ụgbọala Reconnaissance. Ha malitere n'June 10, 1915, ha bu n'obi ịgafe Moline, Iowa City, Omaha, Denver, na Salt Lake City iji ruo San Francisco maka Ngosi Panama-Pacific na July 14, 1915.