will be no dan- The invention relates to expanding screw addressed to the patentees, at their works No. ger by the slacking of the nut during the lift- the nut is drawn up, and its wedges force apart fastenings, to be used under conditions in 276 Bowery, this city, where numerous speci- the… … ing through the upper one, to force down one fectly wedged in the opening, and thus secure improved, but it must be very great. bracket is then put on and held up, and the wedge, and draw up the other, and thus ex- the iron bracket, G, as firmly to _the wall as nuts, B B, placed on the bolts, and…
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