By any measure, John Slack was a remarkably obscure man. For many years my Dad and I knew him mostly through a few tax and marriage records from Mason county, Kentucky. Might he have been the father of our ancestor Jacob Slack (1778-1821), who married in Mason county in 1800 but soon after removed to Clermont county, Ohio? There didn’t seem sufficient records to judge.
Certainly John was the right age. He and wife Catherine consented to the marriage of a daughter in Mason county only 5 years before Jacob’s marriage. Of one thing we were certain: Our Jacob, styled “Jr.” in the 1800 tax list, was not the son of another Jacob Slack shown in that same tax list. That Jacob left a will in Mason county, proved 1836, naming son Jacob A. Slack. Jacob A., according to his gravestone, was born in 1793. Thus Jacob Jr. was not the son of Jacob (Sr.), not unless the elder Jacob had two sons named after him.
From Known to Unknown in Maryland
There is a cardinal rule in genealogy to always proceed from the known. In this case Mason and Clermont counties were dead ends, for they produced no information on the relationship if any between John and our Jacob. A third “known”, however, was an apparent Old Line State origin of the family. This was attested by the 1880 census return of our Jacob’s son Reason Slack, which indicated that his father had been born in Maryland. Tantalizingly, Cassandra Slack Sidwell, John’s known daughter (he served as her marriage bondsman in 1804), was stated in an 1883 county history to have been born “on the eastern shore of Maryland”.
Would Maryland records turn up the origins of this family? A search of census records revealed a John Slack in Harford county in 1790 (1 male 16+, 2 males 16-, 9 females) there accompanied by a Jacob Slack (1male 16+, 1 male 16-, 4 females). Marriage records showed that in 1781, Jacob Slack wedded Elizabeth Ramsay in Harford county, consistent with a 1750-1760 range of birth years implied by his 1830 Mason county census record .
Conclusive proof finally came in the form of a deed dated 1816, in which Jacob and Elizabeth Slack, explicitly styled of Mason county, Kentucky, sold a land share in Harford county. Clearly, the 1790 Maryland heads of household must have been the John Slack and Jacob Slack (Sr.) later in Mason county. Furthermore, given that John’s 1790 record included two males under age 16, it was nearly as clear (and could be presumed) that our Jacob, born in Maryland, was his son. True, the family wasn’t really from the eastern shore. But the county history hadn’t been far off, because the beginning of the eastern shore begins with the Harford county border.
Yet the family seemed as obscure in Maryland as it had been in Kentucky. It seemed reasonable to suppose that John and Jacob (Sr.) were brothers, as it explained both their association across two locations and the use of the “Jr.” designation by John’s son Jacob in 1800 to distinguish him from his uncle. But there were few relevant records in Harford county. One notable one, however, was a 1783 listing in Spesutia Upper Hundred in the county, that included John Slack’s household of 9 whites. It was a listing of paupers.
Poverty, The Tie That Binds
In short order we would discover other indicators of impoverishment in the Slack family. One was a late-life record of John, who by 1824 moved from Kentucky to Butler county, Ohio. He located among the squatters along Four-Mile Creek, apparently too poor to buy land. A second indication was chiseled in stone on the grave marker of Jacob (Sr.) in Mason county, a verse beginning “Parentless when but a boy, The Orphan’s fate his share . . .” And a third proved to be key: A record of “Henry Slight” among “languishing prisoners” listed in a 1769 relief act in Maryland, incarcerated in Baltimore county due to debt. Only two years previous to the imprisonment record, “Henry Sleght”, undoubtedly the same man, signed a deed in Baltimore county as a resident, selling a wagon. Again this was an indication of poverty, in that personal property — especially if a means of work — is always the last to be sold.
The year 1769 was the final one Henry could be found, and a portion of Baltimore county became the new Harford county in 1773. Every indication was that he died around then, give or take a few years, leaving sons John and Jacob mired in poverty for lack of an inheritance.
The Bucks County Connection
The Henry Slight/Sleght records, to be sure, did not come as a surprise. The surname “Slack”, my father and I had long known, likely originated in the Dutch “Sleght”. Thus even before the records were located I had recognized the probable equivalence of John and Jacob Slack of Harford and Mason counties, to John and Jacob Sleght, sons of Hendrick Sleght, baptized respectively in May 1746 and July 1757 in Churchville, Bucks county, Pennsylvania.
That 11-year gap matched another conclusion about the Harford/Mason residents, that John was substantially older than his brother Jacob. Thus John had one known daughter married in 1795 and another probable one married in 1793, suggesting that he was married around 1771, whereas Jacob wasn’t married until 1781. Indeed, it was about this time we found record of Jacob’s gravestone in Mason county. Besides the verse it also recorded his death date as 30 March 1836, and his age as 79 years, 0 months. In other words, he was born March 1757, agreeing with the Bucks county baptismal record.
In effect the Baltimore records of Henry simply provided confirmation of an already probable equivalence between the Pennsylvania and Maryland families. Taking all of the evidence together, that equivalence could now be assumed.
A Glittering Past
Henry himself had been baptized in 1706 in New York City, as Hendrick Sleght, the son of Johannes Hendrickse Sleght and his first wife Catryna Jacobse Bergen. He initially moved to Somerset county, New Jersey, but in 1740 removed to Bucks. It is not known what life circumstances led to his ending his life in penury.
Yet with this man and his wife opens a gateway to some of the oldest Dutch families in America. Hendrick married Catalyntje Nevyus, a great-granddaughter of Joannes Nevius (1627-1672). Joannes was a graduate of the University of Leyden; a 1650/1 immigrant to America; the City Secretary of New Amsterdam; and (once the colony had been taken over by the English) the operator of the Brooklyn ferry.
Hendrick himself was the great-great-grandson of Barent Cornelisz Slecht, a 1662 immigrant to New Netherland, descended in the unbroken male line from Floris Dirkszoon, whose 15th century existence in Woerden, Utrecht, Holland, preceded the use of surnames. Other prominent New York and New Amsterdam families in direct ancestral lineage from Hendrick and Catalyntje Nevyus Sleght include the Bergen, Bleijck, Cool, Lieveling, Lubbertsen, Rapelje, Schenck, Van Kouwenhoven, and Van Voorhees families. Parenthetically, one of their ancestors was a native of Djakarta, Indonesia — but that’s a story for another day.
Finding the origins of this family was a matter of persevering through multiple geographic locations, always proceeding from the known, a microcosm of the genealogist’s craft.
 1830 Census of the Western District, Mason co, Ky, p. 234.
All other references for the above statements are given in two volumes. The first is the all-in-one ancestry, The Omnibus Ancestry. That work updates and corrects, in brief form, material in the second much more detailed volume, Ellis Ancestors: Some Immigrants, Colonists, and Pioneers (1994).
Both books are available for download through Lulu.