Items

• [E1518DBH], Letter from Heyden Chemical Works to Thomas Alva Edison, April 6th, 1915
  1915-04-06
• [E1518DCB], Letter from Heyden Chemical Works to Thomas Alva Edison, April 9th, 1915
  1915-04-09
• [E1518DEP], Letter from Heyden Chemical Works to Thomas Alva Edison, April 20th, 1915
  1915-04-20
• [E1518ECC], Letter from Heyden Chemical Works to Thomas Alva Edison, May 17th, 1915
  1915-05-17
• [E1616EBW], Letter from Heyden Chemical Works to Edison Chemical Works and Other Silver Lake Plants, May 31st, 1916
  1916-05-31
• [E1616FAG], Letter from Heyden Chemical Works to Edison (Thomas A.) Inc, June 6th, 1916
  1916-06-06
• [E1616ACT], Letter from Heyden Chemical Works to Thomas Alva Edison, January 31st, 1916
  1916-01-31
• [E1616HAY], Letter from Heyden Chemical Works to Edison (Thomas A.) Inc, August 10th, 1916
  1916-08-10
• [E1616IBA], Letter from Heyden Chemical Works to Edison (Thomas A.) Inc, September 22nd, 1916
  1916-09-22
• [E1616JAA], Letter from Heyden Chemical Works to Thomas Alva Edison, October 2nd, 1916
  1916-10-02
• [HM55BY], Agreement, Heyden Chemical Works, Thomas Alva Edison, December 28th, 1916
  1916-12-28