Johannes Kool was born on 2 Augustus 1877 in Utrecht as son of pub landlord. He moved in December 1898 to Gouda from Utrecht as a “ceramic painter” as part of the recruitment drive by E Estie to get experienced staff. A few weeks later Michel van der Heidt followed him. It is likely they both had worked for Holland Utrecht or Ravensteijn. Soon after J Kool moved back to his parents in Utrecht, in May 1899, but returned to Gouda in October of that year. He might have commuted for these 6 months. He married in 1900 and in August 1904 the family moved to Dordrecht, possibly to work for DKP. In January 1906 they moved back to Gouda for a year. Then from February 1907, the family lived at several addresses in Utrecht until at least 1912, always registering as ceramics painter.
Based on work signed by him he continued to work at PZH until at least the end of 1908 (NP object).