The technical records of Edison's laboratories and shops were kept in a variety of ways throughout the inventor's career, particularly during the years before 1878. His earliest drawings and notes were kept in pocket-sized books or on loose sheets of paper. In one of these pocket notebooks, Edison concludes with the note: "all new inventions I will here after keep a full record." This determination to keep a "full record" of his inventive activity led to the creation of at least two sets of ledger-sized volumes: the four Newark Shop Notebooks that he began in late July and early August of 1871, and the six "Experimental Researches" begun in October 1875, one of which is missing. Two other unrelated volumes were begun in 1873 and also labeled "Experimental Researches." Other notebooks of varying sizes were used to keep the records of Edison’s laboratories and shops at Newark. Some of these are books of original entry, while others are scrapbooks containing a mixture of experimental notes and drawings, production drawings, patent specifications, and, occasionally, newspaper and journal clippings.
After Edison's move to Menlo Park in 1876, he and his staff began using soft-cover tablet notebooks to record their experiments. They subsequently removed the individual pages from many of these tablet notebooks so that material relating to the same subjects could be gathered together and tracings for litigation exhibits. A set of eleven unbound volumes (Volumes 8–18) was created from the pages of these notebooks and from various other loose pages. Page and volume numbers were written on the back of each page, possibly in 1880 when many of the drawings and notes from this set were removed for use as exhibits in the Telephone Interferences. In this collection we have inserted the tracings of pages removed for litigation where they belong in Volumes 8–18. Beginning in November 1878, Edison adopted a 6 x 9-inch of about 280 pages that became the standard notebooks used in his laboratories. In addition, he and his staff continued to use pocket notebooks and very occasionally other sized notebooks. They also generated hundreds of pages of loose notes and drawings that have been put in folders organized by year.