File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14775154134).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14777149672).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14753993496).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14590839860).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14777534455).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14754525686).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14591032247).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14590503747).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14774430461).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14774400291).jpg - Wikimedia Commons

File:Machine drawing; a practical guide to the standard methods of graphical representation of machines, including complete detail drawings of a duplex pump and of a direct-current generator (1914) (14775154134).jpg - Wikimedia Commons