Depicted here is a Hedley Miner's dial compass made by Davis & Son.  In 1850 John Hedley approached John Davis with a new style instrument which was put into production and was widely used by mining surveyors for the next 100 years.

Davis Derby was a family business established in Leeds (England) in 1779 by Gabriel Davis as a manufacturer of optical, surveying and mathematical instruments.  Gabriel Davis' nephew, John Davis, was born in the village of Thame in Oxfordshire in 1810.  He became apprenticed to J. Abrahams who was known as the Mathematical Instrument Maker to the Duke of Wellington.  Upon completion of his apprenticeship, John Davis moved to Leeds to join his uncle's family business.  Prior to 1830 is was customary for tradesmen to open a shop in a town and then move on to another, covering perhaps ten towns in a circuit.  John Davis followed this trend visiting Liverpool, Cheltenham and making his first visit to Derby in April 1830 where he set up a temporary shop in Rotten Row to sell the company's products where he remained for six weeks.  For the next few years, John visited Derby at regular intervals staying for a few months at a time, advertising his visits in the Derby Mercury.

By 1833 it was clear that John Davis had broken away from the Leeds business of Gabriel Davis and was working for himself.   His company was manufacturing a variety of surveying instruments such as Theodolites, Surveying Dials and Miner's dials, some very similar to the products of Gabriel Davis' business in Leeds.  In 1840, John Davis began manufacturing mining equipment.  The company soon attracted interest from a number of mining experts and quickly became famous in mining circles as a pioneer in the use of electricity in mines and for his mining products.  With the desire to finally settle down with his wife and family, John Davis took up residence in Derby in 1843.

John became the father of ten children, including seven sons.  His two eldest sons, Frederick and Alfred, were both trained as civil engineers.  Upon the death of John Davis in 1873, his son Henry Davis was appointed by his brothers to run the business.  The company continues to this day under the name of Davis Derby LTD and now specializes in electronic equipment for hazardous and demanding environments.

Source information from Mr. David J. Hind