A company founded in 1887 by Salmon & Gluckstein tobacco company, and named after the man appointed to run the company, Joseph Nathaniel Lyons.
It was involved in a range of hotel and food related contexts, but was most familiar to the public for the Lyons tea houses and corner shops.
The company was instrumental in pioneering a range of business computers - LEO range (see kzwp.com/lyons/leo.htm).
It was eventually broken up and incorporated into other companies.
One of its employees was Margaret Roberts, later Thatcher.
The Wikipedia article is at J. Lyons and Co..