The destruction of the standard measurements led to an overhaul of the British weights and measures system. An inquiry that ran from 1838 to 1841 considered the two competing systems used in the country, the avoirdupois and troy measures, and decided that avoirdupois would be used forthwith; troy weights were retained solely for gold, silver and precious stones. The destroyed weights and measures were recast by William Simms, the scientific instrument maker, who produced the replacements after "countless hours of tests and experiments to determine the best metal, the best shape of bar, and the corrections for temperature".