(Robert), a learned and pious English gentleman, was the son of Mr John Nelson a considerable Turkey merchant, and was born in June 1656. He had the first part of his education at St Paul's school, London; but the principal part was under a private tutor in his mother's house, after which he studied at Trinity College, Cambridge. In 1680 he was chosen a fellow of the Royal Society; being probably inclined to receive that honour out of respect to his friend and school-fellow Dr Edmund Halley, for whom he had a particular regard, and in whose company he set out in his travels abroad the December following. In the road to Paris, they saw the remarkable comet which gave rise to the cometical astronomy by Sir Isaac Newton; and our author, apparently by the advantage of his fellow-traveller's instructions, sent a description of it to Dr, afterwards Archbishop Tillotson, by whom he was very much esteemed. Before he left Paris, he received a letter from a friend in the English court, inviting him to purchase a place there, by the promise of his assistance in it. This proposal was made by Mr Henry Savile, brother to Lord Halifax: he had been sworn vice-chamberlain of the king's household in December 1680, and was at this time envoy from Charles II. to the court of France; though now at London, whence he sent this offer in a letter to Mr Nelson; who being but young, and having a great affection for King Charles and the duke of York, was pleased with the thoughts of figuring it near their persons; but as he could not resolve upon an affair of such consequence without the approbation of his mother and uncle, he first applied to Tillotson to sound them, with assurances of determining himself by their judgment and advice, including also that of the Dean; who finding them both adverse to it, he thereupon dropped the matter, and pursued his journey with his fellow-traveller to Rome. Here he fell into the acquaintance of Lady Theophila Lucy, widow of Sir Kingmill Lucy of Broxburne in Hertfordshire, bart. and second daughter of George earl of Berkeley, who soon discovered a strong passion for him: this concluded in marriage, after his arrival in England in 1682. But it was some time before he confessed to Mr Nelson the change of her religion; which was owing to her acquaintance with Bouquet and conversations at Rome with Cardinal Philip Howard, who was grandson of the earl of Arundel, the collector of the Arundelian marbles, &c. and had been raised to the purple by Pope Clement X. in May 1675. Nor was this important alteration of her religious sentiments confined to her own mind, but involved in it her daughter by her first husband, whom she drew over to her new religion; and he zeal for it prompted her even to engage in the public controversy then depending. She is the supposed author of a piece written in 1686, 4to, under the title of, "A discourse concerning a judge of controversy in matters of religion, showing the necessity of such a judge."

This misfortune touched her husband very nearly. He employed not only his own pen, but those of his friends Dr Tillotson and Dr Hickes, to recover her; but all proved ineffectual; and she continued in the communion of the church of Rome till her death. She was a person of fine sense and understanding. Dr Tillotson particularly laments her case on that account; and even seems not to be entirely free from all apprehensions of the influence she might have upon her husband in this important affair. But Mr Nelson's religion was too much the result of his learning and reason to be shaken by his love, which was equally steady and inviolable. Her change of religion made no change in his affections for her; and when she relapsed into such a bad state of health as obliged her to go and drink the waters at Aix, he attended her thither in 1688: and not liking the prospect of the public affairs at home, he proceeded to make a second trip to Italy, taking his lady, together with her son and daughter by her former husband, along with him. He returned through Germany to the Hague, where he laid some time with Lord Durfey, who was married to his wife's sister.

From the Hague he arrived in England, in the latter end of 1691; where being adverse to the Revolution, he declared himself a nonjuror, and left the communion of the church of England. In this last point he had consulted Dr Tillotson, and followed his opinion, who thought it no better than a trick, (detestable in any thing, and especially in religion,) to join in prayers where there was any petition which was held to be sinful. Thus, notwithstanding their difference of opinion respecting the lawfulness of the revolution, the friendship between them remained the same; and the good archbishop expired in his friend's arms in 1694. Nor did Mr Nelson's friendship end there: he continued it to his grace's widow, and was very instrumental in procuring her pension from the crown to be augmented from £400. to £600 per annum. It is very remarkable, that the great regard he had always shown to Tillotson, added to his own reputation for learning, judgment, and candour, induced Dr Barker, who published the archbishop's posthumous sermons, to consult our author on that occasion. Among the manuscripts, there was found one discourse wherein the archbishop took an occasion to complain of the usage which he had received from the nonjuring party, and to expose, in return, the inconsistency of their own conduct; remarking particularly, that, upon a just comparison of their principle of non-resistance with their actual non-assistance to king James II. they had little reason to boast of their loyalty to him: and yet, severe as this discourse was upon that party, Mr Nelson, notwithstanding his attachment to them, was very zealous to have it printed, alleging, that they deserved such a rebuke for their unjust treatment of so good a man. However, the sermon was then suppressed, and is now probably lost.

Our author's new character unavoidably threw him into some new connections. Among these we find mentioned particularly Mr Kettlewell, who had resigned his living at Colehill in Warwickshire on account of the new oaths, and afterwards resided in London. This pious and learned divine also agreed with him, in leaving the communion of the established church; yet at the same time persuaded him to engage in the general service of piety and devotion; observing to him, that he was very able to compose excellent books of that kind, which would be apt to do more good as coming from a layman. This address Nelson corresponded with the truly catholic spirit of our author; who accordingly published many works of piety, which are deservedly esteemed. Indeed it was this spirit, more than their agreement in state principles, that first recommended them to one another. Mr Nelson is observed to have encouraged Kettlewell to proceed in that soft and gentle manner, in which he excelled, in managing the nonjurors' controversy; and animated him besides to begin and prosecute some things for a public good, which otherwise would not have been the light. Mr Kettlewell died in 1695, and left Mr Nelson his sole executor and trustee; in consequence of which, he published a posthumous piece of piety, intitled, "An Office for Prisoners, &c." in 1697. He also published five other of his friend's posthumous pieces, and furnished the chief materials for the account of his life afterwards.

At the same time he engaged zealously in every public scheme for the honour and interest, as well as for propagating the faith, and promoting the practice, of true Christianity, both at home and abroad; several proposals for building, repairing, and endowing churches, and charity-schools particularly.

Upon the death of Dr William Lloyd, the deprived bishop of Norwich, in the end of the year 1709, he returned to the communion of the church of England. Dr Lloyd was the last surviving of the deprived bishops by the Revolution, except Dr Kenn, by whose advice Mr Nelson was determined in this point. It had been a case in view some time, which had been bandied on both sides, whether the continuance of their separation from the church should be schismatical or no, when that case became a fact; and our author had some conferences upon it with Dr Hickes, who was for perpetuating the nonjuring church, and charging the schism upon the church established. (See an account of this dispute, with some letters that passed between them on the occasion, in "The Constitution of the Catholic church, and the nature and consequences of Schism set forth, in a collection of papers written by the late George Hickes, D.D. 1716, 8vo.") Mr Nelson's tutor, Dr George Bull, bishop of St David's, dying before the expiration of this year, he was easily prevailed upon by that prelate's son to drawn up an account of his father's life and writings, as he had maintained a long and intimate friendship with his lordship, which gave him an opportunity of being acquainted with his solid and substantial worth. The life was published in 1713; and as our author had long before laboured under a constitutional weakness, which had brought on an asthma and dropy in the breast, the distemper grew to such a height soon after the publication of that work, that, for the benefit of the air, he retired at length to Kensington, where he expired on the 16th of January 1714-15, aged 59.

He was interred in the cemetery of St George's chapel, now a parochial church in Lamb's Conduit Fields, where a monument is erected to his memory, with a long and elegant Latin inscription, written by Bishop Smallridge. He was the first person buried in this cemetery; and as it was done to reconcile others to the place, who had taken an unfathomable prejudice against it, so it proved a most prevailing precedent, and had the desired effect. He published several works of piety, and left his whole estate to pious and charitable uses, particularly to charity-schools. A good portrait of him was given by Mr Nichols, in 1779, to the company of stationers, and is placed in the parlour of their public hall. After the death of Sir Berkeley Lucy, Mr Nelson's library was sold by auction in 1762, together with that of Sir Berkeley, forming, united, a most extraordinary assemblage of devotion and infidelity. Several of Mr Nelson's original letters, highly characteristic of his benevolence, may be seen in the Anecdotes of Bowyer. Mr Nichols has also in his possession in MS. two excellent letters of advice from Mr Nelson to his young cousins George and Gabriel Hanger, on their going to settle in Turkey; which have been obligingly offered for the use of any future biographer, but are too long for our limits.