He returned to England by way of France, having but six sous in his pockets when he reached Bordeaux, where an English merchant, a total stranger, advanced him a few pounds. On the road, he was frequently taken for an Irishman, and not seldom for an Irish priest; under which impression, many civilities were paid him by the simple inhabitants of the country he traversed. Ultimately he landed at Southampton, with just four shillings in his possession: his once black coat having turned a rusty brown, his hat shovel-shaped by ill-usage, and his whole aspect so comical, that the mob hooted him, under the belief that he was a Methodist preacher. Proceeding inland on foot, in the direction of Southampton, he overtook a poor man walking along the road, whose looks of unutterable misery induced our traveller to stop and inquire what ailed him. He told Jackson he had a son and daughter dying of a disorder apparently contagious, and that no physician would attend them, as he was too poor to pay the fees. Jackson at once offered his services, which were gratefully accepted. He saw his patients, and prescribed for them, and his heart was touched by their simple expressions of gratitude. "Their thankfulness," he says, "for a thing that would perhaps do them no good, gave me more pleasure than a fee of, I believe, twenty guineas, much in need of it as I was." The night had gathered in before he reached Winchester, where, at a respectable inn, he partook of such refreshment as his means afforded, and then desired to be shown to his bedroom. The answer was, that the house contained no bedroom for such as he, and he was finally driven out with the coarsest abuse into the streets. The hour was ten o'clock, the month December, and the severity of the weather may be guessed from the fact, that the snow lay deep on the ground. After wandering about for some time, he at last obtained shelter in a small house in the outskirts of the city. The next day he fared little better. "On Sunday morning," he relates, "I was sixty-four miles from London, and had only one shilling in my pocket. I was hungry, but durst not eat; thirsty, and I durst not drink, for fear of being obliged to lie all night at the side of a hedge in a cold night in December. After dark, I travelled over to Bagshot; was denied admittance into some of the public-houses, ill used in others." He sought in vain permission even to lie in a barn; but a laborer he fortunately fell in with conducted him to a house, where, at the sacrifice of his last shilling, he secured at length a bed. The next day—foot-sore, penniless and starving—he entered London. After remaining there a brief space—January, 1784—in spite of the inclement season, he set off, again on foot, to Perth—a journey that occupied him three weeks, as he was detained on the way by some friends whom he visited. At Perth, where his old regiment then lay previous to its disbandment, he amused himself by studying Gaelic, and the controversy respecting Ossian and his poems. Quitting Perth, he travelled, still on foot, through the Highlands, the inhabitants of which he was, in the first instance, disposed to class with savages; but when he had observed the originality of conception, the breadth of humor, and the elevated sentiments which mark the Celt, his opinions underwent a total revolution. He was especially delighted with a ragged old reiver or cattle-lifter whom he encountered, and who had given shelter to the Young Chevalier in the braes of Glenmoriston after the battle of Culloden.
On his return to Edinburgh, Jackson married a lady of fortune, the daughter of Dr. Stephenson, and niece of his old friend Colonel Francis Shelley, of the 71st regiment; and was enabled by this accession to his means once again to visit Paris, where he not only resumed his medical studies, but acquired the mastery of several languages, Arabic amongst the rest. Having graduated M. D. at Leyden, he came back again to England, and commenced practice at Stockton-upon-Tees, in Durham. Although his reputation speedily became considerable, especially in cases of fever, he seems scarcely to have liked his new avocation. He found solace, however, in his favorite study of language, which he pursued with unremitting ardor—constantly reading through the Greek and Latin classics, and not only rendering himself familiar with the best works of the modern continental authors, but also with the literature of the Arabic, Persian, Hebrew, and Gaelic tongues. The Bostan of Saadi is said to have been one of his most favorite poems.
On the war breaking out in 1793, Dr. Jackson—who, in 1791, had published a valuable work on the fevers of Jamaica and continental America—applied for employment as army-physician; but Mr. Hunter, the director-general of the medical department of the army, considering none eligible for such employment who had not served as staff or regimental surgeon, or apothecary to the forces, Jackson agreed to accept, in the first instance, the surgeoncy of the 3d Buffs, on the understanding, that at a future time, he should be nominated physician as he desired. Mr. Hunter, however, ever, died soon after this; and his promise was not fulfilled by the Board which succeeded him in the medical direction of the army, and which appears to have pursued Dr. Jackson with uniform hostility.
Returning to England with the troops, it was offered to him to accompany, in the capacity of chief medical officer, Sir Ralph Abercromby's expedition against some of the West India islands; and although no employment could possibly have been more agreeable to his taste, he, much to Sir Ralph's chagrin, declined the flattering proposal, on the grounds, that lower terms had been offered to him than to another professional man. Nothing but a sense of professional delicacy, it is plain, governed him in this transaction, for he immediately afterwards embarked (April, 1796) as second medical officer in another expedition to San Domingo. During his abode in this island, he was unwearied in enlarging his acquaintance with tropical diseases—observing the rule he had followed in Holland of noting down by the patient's bedside the minutest particulars of every case he attended, the effects of the treatment pursued, and whatever else might shed light on the intricacies of pathological science. He also gave a larger practical operation to the scheme he had years before devised of amending the dietaries of military hospitals.
After the evacuation of San Domingo in 1798, our physician paid a visit to the United States, where he was received with signal distinction, his reputation having preceded him. The latter part of the year found him again at Stockton, publishing a work on contagious and endemic fevers, "more especially the contagious fever of ships, jails, and hospitals, vulgarly called the yellow-fever of the West Indies;" together with "an explanation of military discipline and economy, with a scheme for the medical arrangements of armies." He undertook, about this time, by desire of Count Woronzow, the Russian ambassador, the medical charge of seventeen hundred Russian soldiers, who were stationed in the Channel Islands in a sad state of disease and disorganization; and so admirably did he acquit himself, and so perfect were the hospital provisions he made, that (1800) the commander-in-chief nominated him physician and head of the army-hospital depôt at Chatham—as he says, "without any application or knowledge on his part." This appointment was the cause of his subsequent misfortunes.
At Chatham, with the warm approbation of Major-General Hewett, commanding the depôt, he introduced that system of hospital reform form which had elsewhere operated so successfully. The changes he effected, as soon as they were made, became known to the Medical Board, and were publicly approved of by one of its members. However, shortly afterwards, an epidemic broke out in the depôt (then removed to the Isle of Wight), arising from the fact, that the barracks were overcrowded with young recruits, but which the medical board ascribed to Jackson's innovations, and reported so to the Horse-Guards. The commander-in-chief directed an inquiry to take place before a medical board impannelled for the purpose, and the result of that inquiry may be guessed from a communication made by the War-Office to the commandant of the depôt. This states "the unanimous opinion of the board to have exculpated Dr. Jackson from all improper treatment of diseases in the sick," and the commander-in-chief's gratification, "than an opportunity has thus been given to that most zealous officer of proving his fitness for the important situation in which he is placed." The result of this wretched intrigue, however, was that Jackson, disgusted with the whole affair, requested to be placed on half-pay, to which request the Duke of York, with marked reluctance, at last (March 1803) acceded.
In his retirement at Stockton, Jackson put forth two valuable works, one on the medical economy of armies, and another on that of the British army in particular, and was much gratified by an offer to accompany, as military secretary, General Simcoe, just appointed commander-in-chief in India. The general's sudden death, however, put an end to this plan; and Jackson continued at Stockton, addressing frequent representations to government on the defective medical arrangements in the military service—representations the very receipt of which were not acknowledged by Mr. Pitt, to whom they were forwarded. The Peninsular war commencing, Dr. Jackson was again named Inspector of Hospitals, but was not, thanks to the persevering enmity of the Medical Board, sent on foreign service, although he volunteered to sink his rank, and go in any capacity. The Board even succeeded, by calumnious statements, that he had purchased his diploma—statements he readily confuted—in preventing his appointment to the Spanish liberating army; although the British government had formally requested him to accept such an appointment, and agreed to give credentials testifying to his capacity and trustworthiness. This last appointment led him, in an unguarded moment—peppery to the last—to inflict a slight personal chastisement on the surgeon-general, for which he was imprisoned six months in the King's Bench.
But the triumph of his enemies was not of long duration. In 1810 the Board was dissolved, and the control of the medical department vested in a director-general, with three principal inspectors subordinate to him. Then did Jackson return to active service, and from 1811 to 1815 was employed in the West Indies; his reports from whence embracing every topic relating to medical topography, to sanitary arrangements, and to the observed phenomena of tropical disease, are, it is not too much to say, invaluable. His hints as to the choice of sites for barracks, the propriety of giving to soldiers healthy employment and recreation, as a means of averting sickness, his suggestions as to the treatment of fevers and other endemic diseases, may be found in the various works he has published, embodying the fruits of his West Indian experience.
In 1819, he was sent by government to Spain, where the yellow-fever had broken out, and his report upon its characteristics has been universally admitted to supply the fullest information on the subject that had hitherto been communicated to the public. He availed himself of his presence in that part of Europe to pay a visit to Constantinople and the Levant; and, retaining his energy to the last, when a British force was sent to Portugal in 1827, he desired permission to accompany it. The sands of his life, however, were then fast running out, and on the 6th of April in the same year he died, after a short illness, at Thursby, near Carlisle, in the seventy-seventh year of his age. Thus closed a long career of usefulness; for it is not too much to say, that few men of his time labored harder to benefit his fellow-creatures than did Dr. Robert Jackson.