S
WCheck valve
WLaunch-type boilerA
WSteam dome
WFire-tube boilerB
WFirebox (steam engine)
WFirebox (steam engine)C
WFusible plug
WW & J Galloway & SonsD
WFirebox (steam engine)
WSafety valveE
WSmokebox
WSnifting valveF
WSoot blower
WSteam drum