installation vs supply depot

installation

noun
  • A grouping of facilities that constitute a permanent military base. 

  • Something installed, especially the whole of a system of machines, apparatus, and accessories, when set up and arranged for practical working, as in electric lighting, transmission of power, etc. 

  • An act of installing. 

  • A work of installation art. 

supply depot

noun
  • A facility utilized by armies to store battlefield supplies temporarily on or near the front lines until they can be distributed to army units. 

How often have the words installation and supply depot occurred in a corpus of books? (source: Google Ngram Viewer )