When the artificial sea-level waterway, Suez Canal, was being constructed (1858-1869), France had dominant control over it. Not surprisingly, England had then vociferously opposed the construction. But later in 1875, sensing a great opportunity, England gained control of the canal, conveniently going against its original stance in the process.
But this twist in the tale opened the floodgates of prosperity for Mumbai.
How?
The earlier detour from Africa had placed the distance between Mumbai and London at 17,700 km, the Suez brought it down to 11,200 km. This meant now the travel time between London and Mumbai was now a mere 25 days which reduced even more with the passage of time. On the old route, London-Mumbai and London-Calcutta (Kolkata) were equidistant, now the Suez got Mumbai closer.
This proximity to London spelt rich rewards for Mumbai - employment opportunities zoomed, textile mills mushroomed, and Mumbai soon became India's premier city. Later, when the canal's depth was extended, a dock for the bigger motorboats was built in Mumbai: the Alexandra Dock (now rechristened Indira Dock)
Beyond doubt, Mumbai owes a lot to the great canal that connects the Mediterranean Sea with the Red Sea through the Isthmus of Suez, and separates the African continent from Asia.