VIII ILLUSTRATIONS. 
Plate XX. A, Loosening of arch stones and spalling of columns by earthquake ; 
B, Undamaged reen forced-concrete structure. 
XXI. A, Lacking of newly constructed building; B, Good earthquake 
endurance of buttressed walls. 
XXII. A, X cracks in brickwork, caused by rocking; B, Slip of founda- 
tion of cyclorama, causing collapse of the structure. 
XXIII. A, Earthquake effect on structure of reen forced concrete of poor 
quality; B, Effect of earthquake on adjacent buildings of dis- 
similar type and construction. 
XXIV. A, Failure of cast-iron shell of concrete-filled cast-iron columns by 
fire ; B, Spalled granite, Market street entrance of ^Etna Build- 
ing, San Francisco. 
XXV. A, Subsidence of street in front of /Etna Building; B, Fire en- 
durance of concrete. 
XXVI. A, Buckled columns and collapsed floor panel ; B, Incipient fail- 
ure of naked cast-iron column in city hall. 
XXVII. A, Earthquake endurance of reenforced-concrete building; B, 
Failure of terra-cotta column coverings, resulting in buckled 
columns. 
XXVIII. A, Earthquake endurance of a well-constructed brick building; B, 
Failure of ornamental terra cotta. 
XXIX. A, Earthquake cracks in walls of vault; B, Collapse of floor panel 
caused by fall of load from floor above. 
XXX. A, Earthquake damage minimized by special construction, Dewey 
monument, San Francisco; B, X cracks in walls due to rocking 
of building by earthquake, Chronicle Building, San Francisco. 
XXXI. Ruin of the seven-million-dollar city hall, San Francisco. 
XXXII. Complete failure of slow-burning wood construction. 
XXXIII. A, Behavior of steel frame; B, Earthquake damage to stone piers. 
XXXIV. Buckling of columns due to failure of plastered metal-lath fire- 
proofing. 
XXXV. A, Incipient buckling of columns from heat; B, Failure of sus- 
pended ceiling. 
XXXVI. A, Granite columns spalled by fire; B, Buckling of columns due 
to failure- of wire-mesh and plaster fi reproofing. 
XXXVII. A, Stonework spalled by fire; B, Earthquake damage due to light 
walls and bad construction. 
XXXVIII. A, Good earthquake endurance of a building of the monumental 
type ; B, Spalling of stonework by fire. 
XXXIX. A, Wrecked tower and spalled stonework; B, Complete wreck by 
earthquake, due to poor design. 
XL. A, Spalling of enameled brick in light well and failure of fire- 
proofing of window-frame separators ; B, Buckling of basement 
column due to failure of terra-cotta covering in fire. 
XLI. A, Endurance of a well-protected building subjected to severe 
radiant heat; B, Warping of plastered metal-lath covering. 
XLI I. A, Roof trusses damaged by heat, through failure of terra-cotta 
covering; B, Effect of settling of ground subjected to earth- 
quake vibrations. 
XLIII. A, Cracks in masonry, pavilion of post-office; B, Effect of slip, 
Mission street, San Francisco. 
XLIV. A, Cracks in masonry and settling of outer terrace, post-office build- 
ing, San Francisco; B, Effect of earthquake in loosening stone- 
work. 
