Table:
text: United States House of Representatives elections, 1860
Pennsylvania
Pennsylvania
District Incumbent Party First_elected Result_
Pennsylvania 1 Thomas B. Florence Democratic 1848 Retired Democratic Hold
Pennsylvania 2 Edward J. Morris People`s 1856 Re-elected Republican Gain
Pennsylvania 3 John P. Verree People`s 1858 Re-elected Republican Gain
Pennsylvania 4 William Millward People`s 1858 Retired Republican Gain
Pennsylvania 5 John Wood People`s 1858 Retired Republican Gain
Pennsylvania 6 John Hickman Democratic 1856 Re-elected Republican Gain
Pennsylvania 7 Thomas Corwin Republican 1858 Re-elected
Pennsylvania 8 Jacob K. McKenty Democratic 1860 Retired Democratic hold
Pennsylvania 9 Thaddeus Stevens People`s 1858 Re-elected Republican Gain
Pennsylvania 10 John W. Killinger People`s 1858 Re-elected Republican Gain

text: United States House of Representatives elections, 1860
Pennsylvania
Pennsylvania
District Incumbent Party First_elected Result_
Pennsylvania 22 Robert McKnight People`s 1858 Re-elected Republican gain
Pennsylvania 23 William Stewart People`s 1856 Retired Republican gain
Pennsylvania 24 Chapin Hall People`s 1858 Retired Republican gain
Pennsylvania 25 Elijah Babbitt People`s 1858 Re-elected Republican gain

text: United States House of Representatives elections, 1860
Pennsylvania
Pennsylvania
District Incumbent Party First_elected Result_
Pennsylvania 11 James H. Campbell People`s 1858 Re-elected Republican gain
Pennsylvania 12 George W. Scranton People`s 1858 Re-elected Republican gain
Pennsylvania 13 William H. Dimmick Democratic 1856 Retired Democratic hold
Pennsylvania 14 Galusha A. Grow People`s 1850 Re-elected Republican gain
Pennsylvania 15 James Tracy Hale People`s 1858 Re-elected Republican gain
Pennsylvania 16 Benjamin F. Junkin People`s 1858 Defeated Democratic gain
Pennsylvania 17 Edward McPherson People`s 1858 Re-elected Republican gain
Pennsylvania 18 Samuel S. Blair People`s 1858 Re-elected Republican gain
Pennsylvania 19 John Covode People`s 1854 Re-elected Republican gain
Pennsylvania 20 William Montgomery Democratic 1856 Retired Democratic Hold
Pennsylvania 21 James K. Moorhead People`s 1858 Re-elected Republican gain

Question: Which district has a first elected of 1858, a result of retired Republican gains, and an incumbent William Millward in the 1860 United States House of Representatives election from Pennsylvania?