. First century of national existence; the United States as they were and ISBEAKlXli UFF AND UlAlUXfl IOAl,.. UliAUlMl llUl H IILUK lUKUl. NUT hUFFICIEN 1 I>K11U of VEIN Hi ADMIX MLLE TEAMS. 143 ladders or steps arranged for the purpose Ibetween the two tracks. Though the open- jing, as represented, appears insignificant foran important mine, such a slope may extendseveral hundred feet in depth, and manygangways may branch off from it to theright and left, extending several miles un-der ground in nearly straight lines along thecourse of the bed. These, however, to se-cure
. First century of national existence; the United States as they were and ISBEAKlXli UFF AND UlAlUXfl IOAl,.. UliAUlMl llUl H IILUK lUKUl. NUT hUFFICIEN 1 I>K11U of VEIN Hi ADMIX MLLE TEAMS. 143 ladders or steps arranged for the purpose Ibetween the two tracks. Though the open- jing, as represented, appears insignificant foran important mine, such a slope may extendseveral hundred feet in depth, and manygangways may branch off from it to theright and left, extending several miles un-der ground in nearly straight lines along thecourse of the bed. These, however, to se-cure ventilation, must have other slopes com-ing out to the surface, and at these may beother arrangements for discharging the coaland water. In extensive mines the gang-ways are made wide and capacious for thecontinual passing back and forth of the wag-ons drawn by mules. These animals oncelowered into the mine are kept constantlyunder ground, where they arc provided withconvenient stables excavated from the coaland rock. The men continue at work fromeight to ten hours, and in well-ventilatedmines the employment is
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Keywords: ., bookauthorhodgejam, bookcentury1800, bookdecade1870, bookyear1874
