Iron and wooden truss-bridges should be thrown down by breaking the main braces near the piers, or the chords near the centre, by charges placed in a joint if possible. High explosives are particularly valuable for this purpose.

In wooden bridges they may be placed in auger-holes bored for them, and in iron bridges inside the hollow members, between eye-bars, or in other similar places.

107. Tunnels, Canal-locks, and similar constructions must be attacked with large charges, so placed as to temporarily or permanently disable the work, as may be considered necessary. The location of each charge should be determined and its amount computed from these considerations before the destruction is attempted.

A temporary obstruction is frequently all that is necessary or desirable for these works, and the damage done to them should be carefully regulated with a view to their subsequent repair and use.

108. Railroads.—Railroads are temporarily disabled by tearing up the track, making hot fires of piles of ties, placing the rails upon them so that they will heat and bend by their own weight; or, better still, twisting the rails while hot by suitably-shaped steel hooks and wooden levers of the kind devised by General Haupt ([Pl. XII], Fig. 33). Rails so twisted cannot be again used until re-rolled.

109. Rolling-stock.—Railroad cars may be disabled by breaking one or more wheels with sledges, or may be destroyed by burning. Locomotives may be disabled temporarily by carrying away the smaller parts of the mechanism, or permanently by breaking the engine-cylinders with sledges; bursting the boilers or burning out their fire-boxes by drawing out nearly all their water, fastening down the safety-valves, and building a hot fire in the furnaces; or by making a hot fire under them so as to heat and thus bend or warp the reciprocating parts of the machinery.

110. In all hasty demolitions with explosives the charges should be well in excess of those computed by the ordinary rules: first, because the explosives will not be so placed as to act to the greatest advantage; and, second, because the demolition should be immediate and complete.

INDEX.

A
PAGE
Additional operations—intrenched camps,[91]
Advance from first parallel,[84]
Advanced positions,[104]
Advantage lies with attack,[176]
Ammunition,[44], [57], [101]
Angle template,[137], [148]
Approaches,[16]
Approaches, execution of,[20]-3
Approaches, tracing,[18]
Approaches, over-ground,[31]
Ascending galleries,[148]
Armament,[100]
Army of observation,[69]
Artillery, first position,[75], [104]
Artillery, first position opening fire,[67]
Artillery, second position,[81]
Artillery, second position opening fire,[83]
Artillery-fire, opening, by defence,[104]
Assault,[4]
Assault, defence against,[7]
Assault, dispositions for,[5]
Assault of breach,[89]
Attaching a miner,[177]
Attack by mines,[169]-171
Attack by sap,[91]
Attack, close,[107]
Attack, journal of,[97]
Attack, plan of,[78]
Attack, point of,[73]
Attack, successive steps of,[64]
Auger, earth,[138]
Auxiliary frame,[144]
B
Battery, alternative construction,[50]
Battery behind crest of hill,[53]
Battery, breaching,[83]
Battery, construction of,[48]
Battery, constructing centre passage of,[48]
Battery, counter,[82]
Battery, definitions,[42]
Battery, electric,[163]-6
Battery, enfilading,[82]
Battery, exposed sunken,[46]
Battery for field-guns, construction of,[43]
Battery for siege-guns and howitzers,[44]
Battery for siege-guns, ammunition required,[44]
Battery, general requirements of siege,[42]
Battery, location of,[9], [75]
Battery, mortar,[55]
Battery of rifled mortars and howitzers,[83]
Battery on sloping ground,[53]
Battery, sunken, in a parallel,[51]
Battery, tracing the,[47]
Belfort, siege of,[71]-2, [86], [104]
Besieging force, bringing up and posting,[67]
Besieging force, strength and composition,[70]-2
Blasts,[178]
Blasting and demolitions,[178]-84
Blindage-frames or blinds,[156]
Blinded descents or galleries,[38], [156], [170]
Blinded sap,[38]
Blinded sap, traverse by,[35]
Blinds or screens,[45]
Blockade,[1]
Bombardment,[8]
Bombardment, defence against,[10]
Bombardment, defence during,[105]
Bomb-proofs and traverses,[25], [170]
Branches,[170]-72
Breach, capture and crowning of,[89]
Breaching batteries,[83]
Breaching by mines,[176]-7
Breaching galleries,[177]
Breaching the scarp and counter-scarp,[88]
Breaking out a full sap from a parallel,[30]
Breaking out a double sap from a parallel,[33]
Bridge, demolition of,[182]
Bridge, floating—passage of ditch,[40]
Brigade or detachment of sappers,[28]
Bringing up and posting the besieging force,[67]
C
Camps, fortifying,[68]
Camouflet,[120], [167], [171], [172]
Canal locks, demolition of,[183]
Capitulation, the,[109]
Capture and crowning of breach,[89]
Capture and crowning of covered way,[87]
Cases, mining,[139]-41
Chamber, definition,[119]
Chamber, form and location,[160]
Changing direction of double sap,[33]
Changing direction of galleries,[148], [150], [154]
Changing slope of galleries,[149], [155]
Charge, definition,[119]
Charge, excess to be used in demolitions,[184]
Charge for over- or under-charged mines,[125]
Charge for blasts, weight determined,[179]
Charge for blasts, when tamped,[178]-9
Charge for common mines,[122]-4
Charge for mines, placing,[165]
Charge for mines, preparing,[161]
Choice of explosives,[132]
Churn-drill,[178]
Circular place of arms,[31]
Conquered place, occupation of,[93]
Common mine defined,[120]
Common mine volumes and charges,[120]-4
Construction of battery for field-guns,[43]
Construction of battery, sunken,[48]-50
Construction of central passage,[48]
Construction of magazine,[60]
Construction of simple trench,[20]
Construction of trench by flying sap,[22]
Counter-battery,[82]
Cover for bomb and splinter proofs,[23]-25
Cover for magazines,[58]
Covered way, crowning of the,[35]
Crater, definitions,[119]
Crater, assumed form of,[121]
Crater relation between volume and charge,[120]-7
Crater radius, definition,[119]
Crowning the covered way,[35]
Crutch,[154]
D
Dampness, precautions against,[63]
Defence, the,[99]-111
Defence against assault,[7], [105]
Defence against bombardment,[10], [105]
Defence against surprise,[4]
Defence, ammunition for,[101]
Defence, armament for,[100]
Defence by mines,[171]-2
Defence, council of,[98]
Defence during bombardment and assault,[105]
Defence during first period,[103]
Defence during second period,[106]
Defence during third period,[107]
Defence, garrison for,[99]
Defence, journal of,[110]
Defence, opening artillery fire by,[104]
Defence, preliminary considerations,[98]
Defence, preparations for,[101]
Defence, provisions and supplies,[101]
Demi-parallels,[86]
Demolitions, deliberate,[180]
Demolitions, hasty,[181]
Descending galleries,[147]
Detachment or brigade of sappers,[28]
Detonation,[162]
Dispositions for an assault,[5]
Distribution of fuzes in charge,[161]
Distance of line of investment,[70]
Ditch, passage of,[37]
Double sap,[32]
Double sap, breaking out, from a parallel,[33]
Double sap, changing direction of,[33]
Double sap, execution of,[32]
Drainage,[16], [24], [55], [59]
Drawings, working,[151]
Drill-bars and drills,[178]
Dynamite, etc.,[132]-5
Dynamite, freezing of,[165]
Dynamite, tamping,[179]
E
Earth auger,[138]
Electric batteries, wires, and lights,[165]-6
Elevated and sunken batteries,[44]
Elevated magazine,[62]
Embrasures,[53]
Enfilading batteries,[82]
Execution of double sap,[32]
Execution of single sap,[28]
Experimental mines,[125], [131], [133]
Explosion, theory of,[120]
Explosive, charge for blasts,[179]
Explosive, charge for mines,[122]-5
Explosive, choice of,[132]-5
Explosive, expenditure of energy,[120]
Explosive, freezing of,[165]
Explosive, noxious gases from,[133], [158]
Explosive, relative strength of,[131], [179]
Explosive, tamping of,[178]-9
Exposed sunken battery,[46]
F
False frame,[146]
Field kitchens and ovens,[114]
Field-level, description,[136]
Field-level, use,[146], [148], [149]
Filtration of water,[117]
Fire, musketry,[84]
Fire, opening by attack,[76]
Fire, opening by defence,[104]
Fire, opening from second artillery position,[83]
Firing blasts,[178]
Firing and loading mines,[161]-6
Firing-tubes and needles,[178]-9
First artillery position,[75]
First parallel,[78]
First period of the siege,[65]
Flying sap,[20]
Flying sap, construction of,[22]
Fort Wagner,[86]
Form and volume of crater,[121]
Fortifying camps, parks, etc.,[68]
Frames and sheeting compared with cases,[141]
Frames and sheeting, use in shafts,[139]-45
Frames and sheeting, use in galleries,[145]-51
Freezing of high explosives,[165]
Full sap,[28]
Full sap, driving of,[28]
Full sap, breaking out from a parallel,[30]
Fuzes,[161], [164], [166]
G
Galleries, blinded,[156]
Galleries, change of direction of,[148], [150], [154]
Galleries, change of slopes of,[149], [154]
Galleries, definitions and dimensions,[119], [138]
Galleries, direction in attack,[171]
Galleries, distance apart,[170]
Galleries, for breaching,[177]
Galleries, inclined,[147]-9, [155]
Galleries, listening,[170]
Galleries of departure,[150]
Galleries, partly lined,[148]
Galleries, rate of advance of,[157]
Galleries, transverse,[170]
Gallery linings,[139]-41
Gallery with frames and sheeting,[145]-51
Gallery with cases,[153]-6
Garrison of place,[99]
Gases generated in mines,[133], [158]
General requirements of siege batteries,[42]
Globe of compression defined,[120]
Governor of the place,[98]
Guns, field, batteries for,[43]
Guns and howitzers, batteries for,[44]
Guns, ammunition required,[44]-57
Guns for armament,[100]
Guns of first artillery position,[76]
Guns, positions of, to be changed,[106]
Gunpowder, amount per cubic yard,[123], [124], [178]
H
Hasty demolitions,[181]
High explosives compared with gunpowder,[131]-5
High explosives, freezing of,[165]
High explosives, use in blasting,[179]-80
Houses and magazines, demolition of,[181]
Howitzer batteries,[44]
Howitzers for vertical fire,[83]
Huts and shelters,[113]
I
Inclined galleries,[47]
Infantry trenches,[104]
Intrenched camp, attack upon,[91]
Investment,[9], [65]
Investment, distance of line of,[70]-72
J
Journal of the attack,[97]
Journal of the defence,[110]
Jumper,[178]
K
Kitchens and ovens,[114]
L
Landings,[150]-1
Latrines, sinks, etc.,[115]
Line of investment, distance of,[70]
Line of least resistance = L. L. R.,[119]
Listening galleries or listeners,[170]-72
Loading and firing mines,[161]
Location of batteries,[9], [75]
Location of magazine,[58]
Lodgement,[170]
M
Magazines,[57]
Magazines, construction of,[60]
Magazines, cover for,[58]
Magazines, drainage of,[59]
Magazines, elevated,[62]
Magazines, execution of the work upon,[61]
Magazines, location of,[58]
Magazines, mined,[61]
Magazines, precautions against dampness,[63]
Maps,[151]
Masks for batteries, etc.,[45]
Masks, air-tight, for exploring mines,[160]
Maxims, Vauban’s,[94]
Mine defined,[119]
Mine-chamber,[160]
Mine, common,[120]-5
Mine, overcharged and undercharged,[120], [125], [131], [171]-72
Mines of attack,[169], [171]
Mines of defence,[171]-2
Mines, organization of,[169]
Mine tactics,[172]-6
Mined magazine,[61]
Mining, military, object of,[119]
Miner, attaching a,[177]
Miner’s bellows,[137]
Miner’s candlestick,[137]
Miner’s lamp,[137]
Miner’s pick and shovel,[136]
Miner’s rule,[122]
Miner’s truck or car,[137]
Mortar batteries,[55], [83]
Mortars, siege,[57], [107]
Musketry fire,[84]
O
Observatories,[54]
Occupation of conquered place,[93]
Opening fire, attack,[76]
Opening fire, defence,[104]
Opening fire from second artillery position,[83]
Opening the first parallel,[80]
Organization and duties of brigade of sappers,[28]
Organization and tactics of mines,[169]-76
Ovens and kitchens,[114]
Overcharged and undercharged mines,[120], [125], [171]-2
Overground approaches,[31]
P
Parallels,[15]
Parallels, demi-,[86]
Parallels, execution of,[20]-3
Parallel, first,[78]
Parallel, first, opening,[80]
Parallel, first, advance from,[84]
Parallel, second,[85]
Parallel, third, etc.,[86]
Parallel, tracing a,[17]
Parks, camps, etc., fortifying,[68]
Parks and depots,[111]
Partly-lined galleries,[148]
Paris, siege of,[71]-2
Passage, central, of battery,[48]
Passage of the ditch,[37]
Period, first, of siege,[65], [103]
Period, second, of siege,[75], [106]
Period, third, of siege,[86], [107]
Pick and shovel, miner’s,[136]
Pick, miner’s, distance heard,[170]
Placing fuzes in charge,[164]
Placing the charge,[165], [176]
Plan of attack,[78]
Plevna, siege of,[71], [72]
Point of attack,[73]
Posting besieging force,[67]
Posting working parties,[18]
Powder-boxes,[58]
Powder for siege batteries,[44], [57]
Precautions against dampness,[63]
Precautions in blasting,[180]
Preliminary considerations of defence,[98]
Preparations for defence,[101]
Preparing the charge,[161]
Progress of the siege,[12]
Proofs, bomb,[25]
Proofs, splinter,[23], [48], [50]
Provisions and supplies,[101]
Push pick,[136]
R
Radius of explosion,[119]
Radius of rupture,[120], [128], [131]
Railroads, demolition of,[183]
Rate of advance of galleries,[157]
Rate of advance of sap,[29]
Regular approaches,[12]
Requirements, general, of siege batteries,[42]
Returns,[150]-1
Rifled mortars and howitzers, batteries of,[83]
Rolling-stock, demolition of,[184]
S
Sand-bag fork,[13]
Sap, attack by,[91]
Sap, definition,[27]
Sap, blinded,[35]
Sap, breaking out from a parallel,[30]
Sap, double,[32]-3
Sap-fork,[13]
Sap, flying,[20], [22]
Sap, full,[28]-30
Sap, shallow,[31]
Sap-shield,[13], [23]
Sap, traversed,[33]-5
Sap, widening the,[30]
Sapping, definitions, etc.,[27]
Sapping, former methods,[36]
Scraper,[13]
Screens,[45]
Second artillery position,[81]
Second artillery position, opening fire from,[83]
Second parallel,[85]
Shaft, definitions and dimensions,[119], [138]
Shaft à la Boule,[156], [172]
Shaft intervals,[142]
Shaft linings,[139]-141
Shaft mines,[172]
Shaft, sinking, with cases,[152]-4
Shaft, sinking, with frames and sheeting,[141]-5
Shaft in a lodgement,[170]
Shallow sap,[31]
Shelters and huts,[113]
Shield for covering ditch,[38]-40
Shield for driving gallery,[147]
Shovel and pick, miner’s,[136]
Siege, definitions, etc.,[12], [64]
Siege batteries,[42]-53
Siege, first period of,[65], [103]
Siege, second period of,[75], [106]
Siege, third period of,[86], [107]
Siege, length of,[71]
Siege of Belfort, Fort Wagner, Paris, Plevna, and Strasburg,[71], [86], [104]
Simple trench,[20]
Sinking shaft with frames and sheeting,[141]-5
Sinking shaft with cases,[152]-4
Sinks and latrines,[115]
Slope, defined,[119]
Slope-block,[137], [148]
Slope, change of,[149], [155]
Slope, method of fixing,[147]
Squibs,[178]
Splinter-proofs,[23], [48], [56]
Sterilizing water,[117]
Stockades, demolition of,[182]
Strasburg, siege of,[71], [86]
Sunken battery,[45]-53
Supplies and provisions,[101]
Surprise,[2]
Surprise, defence against,[4]
Surrender of the place,[109]
T
Tamping blasts,[178]-9
Tamping mines,[166]
Third period of siege,[86]
Todleben’s rules,[173]
Tools and appliances,[10], [136]
Tracing approaches,[18]
Tracing a battery,[47]
Tracing lanterns, pickets, tapes, etc.,[14]
Tracing parallels,[17]
Transverse galleries or transversals,[170]
Traverse by blinded sap,[35]
Traverse, cube,[34]
Traverses, length of,[34]
Traversed sap,[33]
Trenches,[15]
Trench cavalier,[36]
Trenches, guard of the,[15]
Trench, infantry,[104]
Trench, simple,[20]
Tunnels, demolition of,[183]
U
Underground warfare,[169]
V
Vauban’s maxims,[94]
Ventilation of mines,[158]-60
Vertical fire, batteries for,[83]
Volume and form of craters,[121]
Volume and weight of charge,[161], [181]
W
Wagner, Fort, siege of,[86]
Walls, demolition of,[181]
Water-supply,[116]
Weight and volume of charge,[161], [181]
Wet ditch, passage of,[38]-40
Working drawings,[151]