Germantown PA Paper Mill Records from 1774 - White, Armstrong, Jacobs

Any ideas where I look for employment or indentured servant records for paper mills in Germantown Pennsylvania in 1774.  Looking for information for the White, Armstrong, Jacobs families mentioned in the following info.  

According to the Book:   Historic homes and institutions andgenealogical and personal memoirs of the Lehigh Valley PennsylvaniaBy E. Moore Green, J.W. Jordan, G.T. Ettinger  Sarah Armstrong who married John Jacobs came to this country in 1774 from Ireland after her parents death with her uncle a Mr White.    Mr White was a papermaker and located near Germantown, Pennsylvania and the Jacobs family also resided in this vicinity.   Sarah's brother William Armstrong served in the Revolutionary war and was wounded in the battle ofBrandywine and her nephew was a Major Armstrong of Lewistown.

  The complete quote from the above mentioned book follows:

FRANK JACOBS, a resident of Allentown, Pennsylvania, was born in Reading, same state, a son of Alexander and Maria L. (Bushong) Jacobs, and a lineal descendant of an ancestry who emigrated to this country from either Holland or Wales.

     John Jacobs, the earliest ancestor of whom we have any authentic information, was born in Chester, York county, Pennsylvania, in I769, a son of John Jacobs, who served in the American army during the Revolutionary war. In early manhood he settled at a place known as the Long Hollo\v, in the vicinity of McVeytown. In I787, at the age of eighteen years, he married Sarah Armstrong, the ceremony being performed in Chester county, Pennsylvania. She was born in Derry, Ireland, in I766, and after her parents’ death she came to America with an uncle,Mr. White, in 1774. Mr. White was a paper maker and located near Germantown, Pennsylvania, residing there at the time the battle was ‘ fought, and the Jacobs family also resided in this vicinity. William Armstrong, a brother of Sarah (Armstrong) Jacobs, served in the Revolutionary war and was wounded in the battle of Brandywine; and Major Armstrong, of Lewistown, a man of prominence and influence, was a nephew of Mrs. Jacobs. The following named children were born to John and Sarah Jacobs: William, born December I8, I790, died in infancy; Alexander, born July II, 1792; Elizabeth, born April I2, I794, became the wife of Mr. Lieter; Thomas, born November 26, I 795; John, born October II, I797; James, born September I5, I799; Mary, born August I4. I80I, became the wife of Mr. Norton; Armstrong; born July 17, 1803; William, born January I5, I806; Sarah, born February 2, 1808; and David J., born November 28, 1811, died in 1902.  John Jacobs, father of these children, died in Mifilin county, Pennsylvania, in October, I822, and his wife passed away January 18, I842. Their remains were probably interred in Bratton's graveyard, located on a farm then owned by Andrew Bratton. 

     Thomas Jacobs, third son of John and Sarah Jacobs, who was born November 26, 1795, was the grandfather of Frank Jacobs. His son, Alexander Jacobs, father of Frank Jacobs, married Maria L. Bushong, daughter of Philip Bushong, a descendant of the French Huguenots, and two children were born to them: Walter B., who married Kate A. Kuntz, who bore him three children, now deceased; and Frank Jacobs, mentioned at length in the following paragraph. 

     Frank Jacobs spent the early years of his life in attendance at the public schools of Reading, Pennsylvania, and completed his education in the Presbyterian York Collegiate Institution. He then came to Allentown, Pennsylvania, entered the law office of Robert Wright, and studied under his instruction from I887 to I889. He was admitted to the bar of Lehigh county, June 6, I889, at once established an ofiice of his own for the general practice of law, and is now one of the leading lawyers in the city. In religion, he is a Presbyterian, and in politics, a Republican. He holds membership in the Order of Free and Accepted Masons, and the Livingston Club.

     Mr. Jacobs married Florence L. Lance. daughter of John P. and Kate Lance. Mr. and Mrs. Jacobs have one daughter.