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[1921] 1 Ch 200. The claimant took a Lease of land from the defendant Landlord with the express and known intention of storing explosives on it. The landlord then started to build on neighbouring land; the proximity of the new buildings meant that the claimants could not legally store explosives. The court held that for the landlord to build would amount to aderogation from grant, that is, they would have taken good money to grant a lease which would be of no value to the lessees.