'The Book of Flowers', or 'Short Prayers and Ejaculations', is one of Clare Augustine's most celebrated works. It bears an inscription on its first page that reads 'Convent of Our Lady, St Vincent's Goldenbridge' , which dates the manuscript to after 1856, when Clare Augustine began to teach at the school. It consists of the inscription, title page and twenty illuminated prayers.
The title page is written and decorated entirely in golden letters and golden filigree decoration, which fills every opening. Each page is an illumination of a short prayer or ejaculation 'to which if recited with due contrition and devotion, partial indulgences are annexed'. The prayer itself lies in a gold-framed box in the top left-hand corner of the page. In the case of a one-word prayer, such as 'Mary' it fills the box with its colourful Lombardic capitals and white or gold decoration. In the case of a longer prayer, the first word, or few words, are so treated, and the rest is written in black-letter . The details of the specific indulgences are written in golden black-letter above the prayer and outside the box, disguised amongst the gold acanthus ornament that adorns the top left corner of each page for example, 'An Indulgence of 25 days every time. Each page has a thin gold frame and a flat-coloured background of a pastel shade. Resting on this, and taking up the rest of the illumination, are the flowers of the common rule.
These flowers are completely naturalistic, recognisable as distinct species, and not stylised in any way. It is here that Clare Augustine displays her love of natural forms, never repeating a flower but depicting a different variety for each illumination. Each page is distinct in its treatment of text and choice of image. The flowers are painted as if lying on or above the background, casting a shadow on the flat colour beneath. Though they lie within the outline of the box, they never look confined to this area, and give the impression they might fall out of the page at any moment. (Merciful Hours: Sr Mary Clare Augustine Moore's Illuminated Works. Mary Plunkett. Irish Architectural and Decorative Studies. Vol V111, 2005.)