Under the patronage of his uncle, the 1st earl of Caledon, Alexander developed extensive interests as an East India merchant and proprietor.
In the Commons, Alexander was a silent member of the ‘ministerial legion’.
Alexander returned himself and Josias for Old Sarum at the general election the following month. He voted for the duke of Clarence’s grant, 16 Mar., and possibly the spring guns bill, 23 Mar. 1827. He may have been the ‘Mr. Alexander’ who was among those reported as expressing their regret at the state of the Goderich administration in early 1828.
He and Josias were again returned for Old Sarum at the general election of 1830. It was probably about him that an Irish reformer complained that the shopkeepers and traders of Londonderry, a borough in which Caledon had an interest, ‘stood with their mouths open unable to vote, while the Member for Old Sarum and Sir Abraham Bradley King ... were both lending their "sweet voices" to appoint the Member for Derry’.
