Delisle's 1703 "Carte du Canada ou de la Nouvelle France" is praised as the first map to correctly depict the latitude and longitude of Canada. To accomplish this feat, Delisle – while never having personally visited the New World – devoted seven years to in-depth research. He made several earlier sketches drawn from information extracted from the "Jesuit Relations", and personal relationships with many missionaries and explorers enhanced his ability to gain a rather extensive knowledge of the landscape. He also used calculations of the eclipse to find the precise longitude of Quebec which had, up until that point, only been guessed at. The research behind this map, in addition to its mathematical nature, made it a standard for maps to come. It had a large impact when it was published, underscoring the French strength in New France in the early 18th century, and it stood out as an early example of a more dispassionate, scientific type of map relative to the impressionistic ones of centuries before.