Sims left Tyrone to practise as a physician in London, and with his departure what seems to have been the only contemporary record of epidemics in Ireland ceased. The last quarter of the 18th century in Ireland had probably as much epidemic fever as in England; but it is not until the years 1797-1801 that we again hear of fever and dysentery, on the testimony of the records of the Army Medical Board, of the Dublin House of Industry, and of the Waterford Fever Hospital. At the end of the year 1796 the health of the regiments in Ireland was everywhere good; but in December of that year, and in January 1797, the poor in the towns began to suffer more than usual from fever, and in the course of the year 1797 fever appeared in several cantonments of troops—at Armagh as early as February or March, at Limerick, at Waterford and in Dublin[457]. The summer and autumn were unusually wet, so that the peasantry of the southern and western counties were unable to lay in their usual supply of turf for fuel. In the course of the winter 1797-98 a considerable increase of fever and dysentery was remarked among them, and these two maladies appeared in various regiments in the early months of 1798. This was the year of the rebellion in the south-east of Ireland, pending the efforts for the union with England. The British troops were much engaged with the insurgents throughout the summer, and got rid in great part of the maladies of their quarters while they were campaigning. But in the end of the year fever began to spread, both among the inhabitants and among the troops. It was nothing new for English and Scots regiments to suffer from fever or dysentery during the greater part of their first year in Ireland; but the epidemics in the end of 1798 were more than ordinary. The Buckinghamshire Militia quartered in the Palatine Square of the Royal barracks, Dublin, lost by “malignant contagious fever” 13 men in October, 13 in November, and 15 in December. From November to January, the Warwick regiment suffered greatly in the same barrack. The Herefordshire regiment, 833 strong, lost 47 men at Fermoy, mostly from fever contracted in bad barracks; the Coldstream Guards at Limerick, the 92nd regiment at Athlone, and the Northamptonshire Fencibles at Carrick-on-Shannon, also lost men by fever. In July, 1799, not a single regiment in Ireland was sickly; but a wet and very cold autumn made a bad harvest, aggravating the distresses of the poor and causing much sickness, which the troops shared. The county of Wexford, the principal scene of the rebellion, suffered most, and next to it the adjacent county of Waterford. The fever-hospital of the latter town, the earliest in Ireland[458], was projected in 1799; the statement made in the report of a plan for the new charity, that fifteen hundred dependent persons suffered from contagious fever every year there, showed that the need for it was nothing new, although hardly a tenth part of the number sought admission to the hospital when it was at work. Next year, 1800, the managers of the newly-opened hospital gave some particulars of the causes of fever in Waterford—want of food, causing weakness of body and depression of mind, but above all the excessive pawning of clothes and bedding, whereby they suffered from cold and slept for warmth several in a bed. In the winter and spring of 1799-1800 the poor of Waterford had epidemic among them fever and dysentery, as well as smallpox. In Donagh-a-gow’s Lane nine persons died of dysentery between October 1799 and March 1800. The harvest of 1800 was again a failure, from cold and wet, bread and potatoes being dear and of bad quality. In the autumn and winter the distress, with the attendant fever and dysentery, became worse. At that time in Dublin all fever cases among the poor were received into the House of Industry (the Cork Street and Hardwick Hospitals were soon after built for fever-cases), at which the deaths for four years were as follows:
| Year | Died in the Dublin House of Industry | |
| 1799 | 627 | |
| 1800 | 1315 | |
| 1801 | 1352 | |
| 1802 | 384 |
The enormous rise of the deaths in 1800 and 1801 shows how severe the epidemic of fever must have been. Compared with the epidemic of 1817-18, it has few records, perhaps because the political changes of the union engrossed all attention. But the significant fact remains that the deaths in the Dublin House of Industry in 1800 and 1801 were nearly as many as in all the special fever-hospitals of Dublin during the two years, 1 Sept. 1817 to 1 Sept. 1819. At Cork, in 1800, there were 4000 cases of fever treated from the Dispensary; at Limerick the state of matters is said to have been as bad as in the great famine of 1817-18; and there is some reason to think that the same might have been said of other places. All the relief in 1800-1801 came from private sources, the example of Dublin in opening soup-kitchens having been followed by other towns. The troops shared in the reigning diseases, especially at Belfast and Dublin; in the latter city, the spotted fever was severe both among the military and all ranks of the civil population in August, 1801. The harvest of 1801 was abundant, and the fever quickly declined. It had been often of the relapsing type[459]. Dysentery appeared in the end of September, and became severe in many places in October and November, being attributed to the rains after a long tract of dry, hot weather. Ophthalmias and scarlatinal malignant sore-throats were common at the same time.
The Growth of Population in Ireland.
When the history of the great famine and epidemic sicknesses of 1817-18 was written, it was found that this calamity had fallen upon a population that had grown imperceptibly until it had reached the enormous figure of over six millions, the census of 1821 showing the inhabitants of Ireland to be 6,801,827. The increase from an estimated one million and thirty-four thousand in 1695 was, according to Malthus, probably without parallel in Europe. According to Petty, the inhabitants in 1672 numbered about one million one hundred thousand, living in two hundred thousand houses, of which 160,000 were “wretched, nasty cabins without chimney, window or door-shut, and wholly unfit for making merchantable butter, cheese, or the manufacture of woollen, linen or leather.” In 1695, the war on behalf of James II. having intervened, the population as estimated by South was 1,034,000. When the people were next counted in 1731, by a not incorrect method in the hands of the magistracy and Protestant clergy, they were found to have almost doubled, the total being 2,010,221. This increase, the exactness of which depends naturally upon the accuracy of Petty’s and South’s 17th century estimates, had been made notwithstanding the famines and epidemics of 1718 and 1728, and an excessive emigration, mostly of Protestants, to the West Indian and American colonies, which was itself attended by a great loss of life through disease. For the rest of the 18th century, the estimates of population are based upon the number of houses that paid the hearth-tax. In the following figures six persons are reckoned to each taxed hearth:
| Year | Persons | |
| 1754 | 2,372,634 | |
| 1767 | 2,544,276 | |
| 1777 | 2,690,556 | |
| 1785 | 2,845,932 |
The hearth-money was not altogether a safe basis of reckoning, for the reason that many were excused it on account of their poverty by certificate from the magistrates, and that hamlets in the hills, perhaps those which held their lands in rungale or joint-lease, often compounded with the collectors for a fixed sum; so that cabins might multiply and no more hearth-tax be paid[460]. It is probable that a considerable increase had taken place which was not represented in the books of the tax-collectors; for in 1788, only three years from the last date given, the number of hearths suddenly leapt up to the round figure of 650,000 (from 474,322), giving a population of 3,900,000, at the rate of six persons to a cabin or house. But it is undoubted that a new impulse was given to population in the last twenty years of the 18th century, firstly by the bounties on Irish corn exported, dating from 1780, which caused much grazing land to be brought under the plough, and secondly by the gradual removal, after 1791, of various penalties and disabilities which had rested on the Roman Catholics since the reign of Anne, affecting their tenure of land, and serving in various ways to repress the multiplication of families. Accordingly we find the hearths rated in 1791 at the number of 701,102, equal to a population of 4,206,612. The estimates or enumerations from 1788, to the census of 1831, show an increase as follows:
| Year | Persons | |
| 1788 | 3,900,000 | |
| 1791 | 4,206,612 | |
| 1805 | 5,395,456 | |
| 1812 | 5,937,856 | |
| 1821 | 6,801,827 | |
| 1831 | 7,784,539 |
The secret of this enormous increase was the habit that the Irish peasantry had begun to learn early in the 17th century of living upon potatoes. From that dietetic peculiarity, it is well known, much of the economic and political history of Ireland depends. At the time when it was losing its tribal organization (rather late in the day, although not so late as in the Highlands of Scotland), the country was in a fair way to pass from the pastoral state to the agricultural and industrial. It is conceivable that, if Ireland had peacefully become an agricultural country, wheaten bread would have become the staple food of the people, as in England in early times and again in later times; or that the standard might have been oatmeal in the northern province, as in Scotland: in which case one may be sure that the population would not have increased as it did. “Since the culture of the potatoes was known,” says a topographer of Kerry in 1756, “which was not before the beginning of the last century, the herdsmen find out small dry spots to plant a sufficient quantity of those roots in for their sustenance, whereby considerable tracts of these mountains are grazed and inhabited, which could not be done if the herdsmen had only corn to subsist on[461].” Twenty years later Arthur Young found an enormous extension of potato culture, the pigs being fed on the surplus crop[462]. The motive, on the part of the landlord or the farmer, was to have the peat bogs on the hill-sides reclaimed by the spade; the surface of peat having been removed, a poor subsoil was exposed, which might be made something of after it had grown several crops of potatoes, but hardly in any other way. Another motive was political; namely, the multiplication by landlords of forty-shilling freeholder dependent votes among the Catholics as soon as they became free to exercise the franchise[463].