Editing GWR 2900 Class (section)

===No. 98===
[[File:GWR 4-6-0 No.98.jpg|thumb|left|The second prototype No. 98 as built 1903]]
A second prototype locomotive, No. 98, was built at Swindon Works in March 1903 (Lot 138) to a similar design but with a taper boiler, re-designed valve gear layout and cylinders and a shorter wheelbase.<ref name=RCTS2>{{harvnb |le Fleming|1953 |p=H23}}</ref> Valve diameters were increased from {{convert|6+1/2|in|mm}} to {{convert|10|in|mm}}.<ref name=GWS29xxOvw /> According to Poultney, these improvements "may truly be said to be the keystone of the arch upon which all modern locomotives are designed".<ref name=Poulteney2>{{harvnb|Poultney|1952 |p=66}}</ref> In 1906 this locomotive was re-boilered with a {{convert|225|psi|MPa|2|abbr=on|lk=on}} boiler to correspond with the third prototype. This prototype locomotive was named ''Vanguard'' in 1907 (renamed ''Ernest Cunard'' in the same year). It was renumbered 2998 in 1912, received a [[superheater|superheated]] boiler in 1911 and was withdrawn in 1933.