Light Horse by William Blamire Young, consigned to Christie's via an iPhone.
Light Horse and Artillery, painted in 1904, were an attic find for a Surrey vendor who asked her neighbour for advice on how to sell them.
The neighbour, a digital developer and avid iPhone user, used his Christie's 'app' to research the artist from the signature, and then sent photographs of the works through to the specialist department for a valuation.
The paintings (one of which was documented but its whereabouts unknown) celebrate the birth of the Australian army and were formerly in the ownership of its founder, Major General Edward 'Curly' Hutton.
They will be offered as a pair and are expected to realise £20,000-30,000 when included in the sale of Modern and Contemporary Australian Art at Christie's South Kensington on September 23.
