BENTINCK (WILLIAM HENRY CAVENDISH ), third Duke of Portland, was born on the 14th of April 1738. Having finished his education at Christ Church, Oxford, he went on his travels. Soon after his return, be was elected for the borough of Weobly, in the first Parliament of the King's reign. For this borough, however, he did not sit long ; for, on the death of his father, on the let of May 1762, he was called up to the House of Peers. He imme diately joined the opposition ; and, in 1763, his name is found among the minority against the cyder bill, and along with that of the Duke of Grafton, in a protest against it. The next session, he also signed a protest on the motion to vote away the privilege claimed by members of Parliament in matters oft li bel. In 1765, when his friend the Marquis of Rock ingham came into power, he was appointed Lord Chamberlain, and he retired when the Marquis went out of office. In 1768, there was a violent contest for the county of Cumberland ; and as the Duke warmly supported the two opposition candidates, the ministry, in order to weaken his influence, and at the same time to increase that of Sir James Lowther, who was one of the ministerial candidates, granted to the latter Inglewood forest, an extensive and valuable estate, which had been granted by King William .III. to the first Duke of Portland, and had remained in possession of that family ever since. The new grant was made in consequence of a report from the sur veyor-general of crown lands, that the premises were not comprised in the original grant from King Wil liam to the Duke of Portland, but were still vested in the crown. A letter was written from the Trea sury, directing the Duke to prepare his title, and assurisog him that nothing should be decided con cerning the grant till such title had been stated and maturely considered ; but while his Grace's agents were busily employed in their researches and in quiries, he received a second letter, informing him that the grants were passed, and the leases signed. A caveat had been entered at the Exchequer to stop the progress of the grant, but, when Lord North was prayed to withhold affixing the Exchequer seal, he replied that, as Chancellor of the Exchequer, he was bound to obey the orders of the Treasury.
On the 19th of November 1771, this great cause was tried before the Barons of the Exchequer, in Westminster-Hall. The Court recited all the re cords, and prerogatives of the crown, from Edward I. to the lease made to Sir James Lowther ; when, after a full and impartial examination of the said lease, it was found invalid ; agreeably to the statute of the 1st of Anne, which expressly requires that, upon every grant from the crown, there shall be a reserved rent, not under the third part of the clear yearly value of the manors, lands, &c. as shall be contained in the grant. Sir James Lowther's grant from the crown being only a quit rent of 13s. 4d. for the whole of Inglewood forest, was immediately determined by the Court an inadequate third pro portion, and he was nonsuited accordingly. The nullum tempus bill, or the act for quieting the pos sessions of the subject against all pretences of con cealment whatsoever, which was brought into Parlia ment in 1768, and passed in the following year, owed its rise to this grant of the Portland property to Sir James Lowther.
In 1766. the Duke of Portland had been bound more closely than ever to the Rockingham party, in con sequence of his marriage with Lady Dorothy Caven dish, sister to the Duke of Devonshire. On the re signation of Lord North, he was appointed Lord Lieutenant of Ireland ; and, during his government, the Parliament of that country was declared inde pendent of the British Parliament. After an admi nistration of somewhat more than three months, he was recalled, when Lord Shelburne came into power. On the death of the Marquis of Rockingham, he was recommended by the Privy'Council to the King as his successor at the Treasury ; but Lord Shel burne was preferred. When the Coalition came into power, however, he obtained the situation of Prime, Minister, and went out of office with them. During Mr Pitt's difficulties, when he first came into admi nistration, in consequence of the House of Commons being against him, an attempt was made to form a coalition between him and the Duke of Portland ; but his Grace objected to the conditions on which Mr Pitt came into power, and refused his support, unless he would resign his place, and come in again on equal terms with himself and his friends.