As the Industrial Revolution intensified in the 18th and 19th centuries, the industries of banking, rail, insurance, retail, petroleum, and telegraphy dramatically grew in size and complexity. Increasingly large number of clerks were needed to handle order processing, accounting, and document filing, and these clerks needed to be housed in increasingly specialized spaces. Most of the desks of the era were top-heavy and had a cubicle-like appearance, with paper storage bins extending above the desk-work area, offering workers some degree of privacy.