Shortly after being made Rear-Admiral of the Blue, he was invested with a command which shows the remarkable estimation in which he was held by the Government, receiving, as he did, a commission from the King as Admiral and Commandant of a squadron of six ships of the line and five frigates, with 2,000 soldiers on board, ordered for the East Indies; and also as General and Commander-in-Chief of the land forces employed in the expedition--'the only instance, except that of the Earl of Peterborough, of any officer having received such a command since the reign of Charles II.' Yet, such were his tact and personal character, that no ill-feeling arose on the part of the troops thus placed under his command--in fact, as an officer, quoted by Campbell, quaintly says, 'the Admiral, by his genteel behaviour, gained the love of the land officers, and never was greater harmony among all degrees of men than in this expedition;' notwithstanding which it failed in effecting the main objects which it had in view, viz. the capture of Pondicherry, and the attack on Port Louis, Mauritius, _en route_ thither. He sailed from St. Helen's on the 4th November, 1747; but owing to bad weather and contrary winds, did not reach the Cape of Good Hope till the 29th March, 1748; and here he remained a short time to refresh his jaded crews. The difficulties of the landing at Port Louis, and the strength of the batteries by which it was defended, were such as to triumph over even the genius and courage of Boscawen; and after vain though most strenuous search for a practicable landing-place, the Admiral called a council of war, at which it was determined that a small boat-party should land during the night with a view to capturing (if possible) at least one man of the enemy, from whom they might obtain information as to the numbers and situation of the French forces. This ingenious attempt, however, failed; and at a second council of war it was agreed that the attack on Port Louis, even if it succeeded (which was doubtful), would necessitate the leaving behind so large a force to occupy the place, that it would imperil the chances of capturing Pondicherry, the principal object of the expedition; and to this it may be added that Boscawen had lost many of his men from their eating a poisonous fish called the vieille, at the island of Roderique.