At the beginning of Part VII of his _Review_, which treats of plants, he thrusts very deep. He says, "This is a Branch of Natural Knowledge, which, it will appear, that the Royal Society of London have looked so very deeply into, that their rejecting the Linnean System of Botany, when offered by its Author will no longer be wondered at." In this Part he is particularly severe upon Baker, and, in reading it, one is forced to the conclusion that although adverse criticism was warranted, there was a good deal of personal feeling behind it. This attack on the Royal Society appears to have been much resented, and Hill's credit consequently was much damaged, for it was considered that Folkes and Baker had befriended him in his earlier days. With regard to Folkes it has been seen that Hill considered that he was doing a public duty; and with regard to Baker, Hill suffered under a real or imaginary grievance which, assuming Baker had helped him in the past, cancelled all obligations due from him to Baker. If this be not so then Hill, in addition to his other faults, was lacking in gratitude. With regard to this point his anonymous biographer[70] wrote that "we have nowhere learnt that ingratitude had the smallest share in the composition of the character of Sir John Hill." The attack, however, was not altogether fruitless, as Disraeli[71] remarks, "Yet Sir John Hill, this despised man, after all the fertile absurdities of his literary life, performed more for the improvement of the Philosophical Transactions, and was the cause of diffusing a more general taste for the science of botany, than any other contemporary." It is hardly necessary to remark that Hill was never elected to the Royal Society. * * * * * Thus by his methods of criticism Hill brought to an end a period of highly remunerative literary work; it was therefore necessary for him to seek other pastures. He returned, in part, to the practice of medicine in the shape of herbalist, preparing remedies from various plants such as valerian, water-dock and centaury; also he wrote on the virtues of these and other plants. The source from which he obtained his plants was in the first instance the Chelsea Physic Garden, but it is stated that he was eventually forbidden its use owing to his depredations; later he grew the requisite plants in his own garden which was situated where now is Lancaster Gate. There was a good deal of common sense in his remedies; thus in his _Virtues of British Herbs_ he remarks that "He who seeks the herb for its cure, will find it half effected by the walk." By the sale of his medicines and of his pamphlets relating to medicinal plants, some of which ran through many editions, he made large sums of money.