twelve o'clock precisely
J. T. Maston became their cicerone . He omitted no point of detail ; he conducted them throughout the magazines , workshops , through the midst of the engines , and compelled them to visit the whole 1,200 furnaces one after the other . At the end of the twelve-hundredth visit they were pretty well knocked up . The casting was to take place at twelve o'clock precisely . The previous evening each furnace had been charged with 114,000 pounds weight of metal in bars disposed cross-ways to each other , so as to allow the hot air to circulate freely between them . At daybreak the 1,200 chimneys vomited their torrents of flame into the air , and the ground was agitated with dull tremblings . As many pounds of metal as there were to cast , so many pounds of coal were there to burn .