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History Of The Arts And Sciences For 1797.
The arch of the bridge is formed by hollow frames , each consisting of four sides , with a flat bottom . ' The sides compose the arch joints of the bridge , and are so lessened as to tend to the centre of the circle . When these frames are fitted together , they form the arch , the sides of which have a solid bearing throughout , like those of common bridges . substance
The frames are then filled with sand , or some gravelly , or with rough masonry , or such solid substance as that , when filled , the arch may make one solid body , which is cased w . ' th iron . The frames maybe of cast iron , or wrought iron ; or may be made of fiat iron plates , well put together . They also be cast without bottomsand loose bottoms
aftermay , wards put in ; or they may in fact be used without bottoms at all , or formed of a series of arches , with flanches forming the arch joints , and filled up in the spandrils , or not filled up ; or they may be formed of hollow cylinders , with flanches . The arch joints may have sheet lead , or any . other composition , placed between them , to fill up the irregular surfaces of the iron .
The arch joints may be screwed together ; or stubbs , or tenants , fitted with correspondent holes , mortices , and grooves , may be cast in the plates themselves , and fit into each other . The skirting , or kirb , which keeps in the ground , may be cast , or framed with the frames ; or they may be cast separate , and then put on ; or they may be quite omitted . When twothreeor more arches are put togetherthe spaces
be-, , , tween the arches are formed by hollow spandrils of wrought iron , or cast iron , and framed or cast as already mentioned ; and they may be filled up or not , as the frames before described . These hollow spandrils may be cylindrical , triangular , quadrangular , or polyangular . The piers are formed like the frames , hollow , and may be filled in solid or notand be of late ironeither wrought or castand put
, may p , , together of framed ; and with respect to form it is optional . The piers , formed of hollow iron bodies , are fixed to the bed of the river by hollow plates , nailed to the ground by piles of plate iron , grooved , or dove-tailed into each other ; and they maybe cast with the hollow frames , forming the p iers , or be fastened with
iron . The dam is formed hollow by piles of plate iron , grooved and dove-tailed into each other ; which , when so joined , form a hollow box , and when inserted into the bed of the river , make a dam for the pier ; and when the pier is built , they are driven into the bed of the river , and make a frame of piles , inclosing the ground in which the pier standsand securing it from being undermined by the
, water passing through the arch . ( TO BE COSTIN-UED . ) * * * We shall he thankful to oar scientific and well-informed readers for . accounts of ! ic-jj . inventions and discoveries in the Arts , Sciences , and Manufactures ; or for any communications that may tend to illustrate these important subjects .
Note: This text has been automatically extracted via Optical Character Recognition (OCR) software.
History Of The Arts And Sciences For 1797.
The arch of the bridge is formed by hollow frames , each consisting of four sides , with a flat bottom . ' The sides compose the arch joints of the bridge , and are so lessened as to tend to the centre of the circle . When these frames are fitted together , they form the arch , the sides of which have a solid bearing throughout , like those of common bridges . substance
The frames are then filled with sand , or some gravelly , or with rough masonry , or such solid substance as that , when filled , the arch may make one solid body , which is cased w . ' th iron . The frames maybe of cast iron , or wrought iron ; or may be made of fiat iron plates , well put together . They also be cast without bottomsand loose bottoms
aftermay , wards put in ; or they may in fact be used without bottoms at all , or formed of a series of arches , with flanches forming the arch joints , and filled up in the spandrils , or not filled up ; or they may be formed of hollow cylinders , with flanches . The arch joints may have sheet lead , or any . other composition , placed between them , to fill up the irregular surfaces of the iron .
The arch joints may be screwed together ; or stubbs , or tenants , fitted with correspondent holes , mortices , and grooves , may be cast in the plates themselves , and fit into each other . The skirting , or kirb , which keeps in the ground , may be cast , or framed with the frames ; or they may be cast separate , and then put on ; or they may be quite omitted . When twothreeor more arches are put togetherthe spaces
be-, , , tween the arches are formed by hollow spandrils of wrought iron , or cast iron , and framed or cast as already mentioned ; and they may be filled up or not , as the frames before described . These hollow spandrils may be cylindrical , triangular , quadrangular , or polyangular . The piers are formed like the frames , hollow , and may be filled in solid or notand be of late ironeither wrought or castand put
, may p , , together of framed ; and with respect to form it is optional . The piers , formed of hollow iron bodies , are fixed to the bed of the river by hollow plates , nailed to the ground by piles of plate iron , grooved , or dove-tailed into each other ; and they maybe cast with the hollow frames , forming the p iers , or be fastened with
iron . The dam is formed hollow by piles of plate iron , grooved and dove-tailed into each other ; which , when so joined , form a hollow box , and when inserted into the bed of the river , make a dam for the pier ; and when the pier is built , they are driven into the bed of the river , and make a frame of piles , inclosing the ground in which the pier standsand securing it from being undermined by the
, water passing through the arch . ( TO BE COSTIN-UED . ) * * * We shall he thankful to oar scientific and well-informed readers for . accounts of ! ic-jj . inventions and discoveries in the Arts , Sciences , and Manufactures ; or for any communications that may tend to illustrate these important subjects .