Horstmann Gear Co
of Newbridge Works, 93 Newbridge Road, Bath, Somerset. (1922)
Ditto Address: Telephone: Weston (Bath) 7241/2. Telegraphic Address: "Horstmann, Bath". (1937)
1902 A clockwork gas controller was introduced for the automatic control of street lighting for the Bath Gas and Coke Co.
1904 The brothers patented the Solar Dial which automatically adjusted lighting times at dusk and dawn throughout the year. It was the start of nearly eighty years of Horstmann's manufacturing involvement in the street lighting controls market.
The gearbox was not a success, but Sidney went on to make cars in his own business, also in Bath, producing about 1500 Horstman Cars between 1913 and 1929, incorporating many novel features in them. Altogether about 10 still exist.
WWI The supply of German clock movements for gas controllers ceased; Horstmann's developed their own. They were then directed by the government to switch production to screw and limit gauges for manufacturing munitions, becoming a leading UK gauge manufacturer.
1915 The Newbridge Works was opened. The trade name Newbridge was then used on most of the company's products.
Postwar: New products developed such as gardening tools, domestic clocks, mousetraps and cages for transporting and mailing queen bees. The main markets continued in street lighting controls, gas ignition, time switches and gauges.
1922 Listed Exhibitor - British Industries Fair. Manufacturers of Scientific Models, Industrial Testing Apparatus, Clocks, Cases for Clocks. (Stand No. E.42) 
1925 G. Horstmann and Sons’s retail business in Union Street closed after 41 years on the premises and 73 years as watchmakers, jewellers and retailers.
Developed a gas controller which could be replaced in situ without disconnecting the gas supply, controllers for electric lighting, synchronous motor driven time switches, the Comet gas ignition device, the Gas Pistol for lighting gas ovens or cooking rings, the Distant Gas Switch equivalent to an electric light switch, and a patented thread gauge.
1930 Ernst Hermann Horstmann, Secretary and Managing Director of Horstmann Gear Co died aged 63
1937 Listed Exhibitor - British Industries Fair. This exhibit comprises the complete range of Newbridge Automatic Lighting Appliances. Controllers (for all types of Lamps), "Comet", Igniters, Switches for Domestic Lighting, and Gas Fires, Gas Pistols, Pressure Governors, etc. (Stand No. Ca.508)
1937 Listed Exhibitor - British Industries Fair. Newbridge Type 5/3/Enc. (Main Tap Controller for industrial purposes, made in 1in. and 2in. sizes, for interior and exterior use. Newbridge Service Pressure Governor. Full particulars and demonstrations on Stand Ca.508. (Stand Nos Ca.709 and Ca.608) 
1939 the first system for timing central heating was introduced.
WWII Made the Astro compass, mine switch-clock, radio transmitter for aircraft direction finding.
1948 The Horstmann Gear Co was voluntarily wound up
1948 Private company.
Introduction of electric and gas-fired central heating controls; automatic ignition for cookers, and timers for 'off-peak' electricity.
1955 Horstmann Gear Co started making veterinary equipment, first a bloodless castrator and a unique spring action earmarker, which was very successful
c.1955 Several products for vets were introduced by Horstman Ltd but this product range was sold off later.
1961 Precision engineers and manufacturers of precision gauges, time switches (gas and electric), automatic ignition devices, gas cooker lighters. 600 employees. 
Purchased Rogerstone Precision Ltd. near Newport, previously a major supplier of components to Horstmanns
1970s Supplied gas igniters and cooker lighters for the replacement appliances when North Sea gas was introduced. Acquired Aish and Co Ltd. of Poole, specialists in marine equipment.
1978 Reorganisation of the company. Established Horstmann Timers and Controls Ltd which replaced the Instrument Division; the Company changed its name to Horstmann Gear Group Ltd. Horstmann Engineering Products Ltd was created to develop new energy conservation products for commercial applications, which also took over the street lighting controls business.
1980s Supplier of controls for Economy 7 tariff and radio teleswitch
Acquired a controlling interest in Serck Controls Ltd.
1988 Aish was sold.
1991 The street lighting controls business was sold to Royce Thompson.
1994 The family sold their remaining interest; Horstmann Group became part of Clayhithe plc.
2000 Relocated to purpose-built premises in Bristol
2001 Management Buy Out of Horstmann Controls.
2007 Focussed on:
- Controls for Central Heating Systems
- Electric Heating
- Utility metering