Speculum spiritualium (The Spiritual Mirror) is an anonymous religious compilation written in Latin, made between 1400 and 1430.
[1] The work was relatively popular, known in at least a dozen manuscripts, and printed by Wynkyn de Worde in 1510.
Henry de Balnea was invented by Thomas Tanner as another author for the work.
The author quotes Walter Hilton repeatedly, and refers to him as 'uenerabilis', implying the work was composed after his death in 1396.
Adam Horsley is thought to be the most plausible identification, since he is known to have been acquainted with Walter Hinton.