(_f_) Furthermore, although that spurious work has a chapter _De elementis_, it reveals none of Hildegard’s most peculiar and definite views as to their nature, origin, and fate,[28] nor does it refer to the sphericity of the earth, to the vascular system of man, to the humours and their relation to the winds and the elements, or to a dozen other points on which, as we shall see, Hildegard had views of her own. Before leaving the subject of Hildegard’s apocryphal works, brief reference may be made to the _Speculum futurorum temporum,_ a spurious production to which her name is often attached. It exists in innumerable MSS., and has been frequently edited and translated. It is the work of Gebeno, prior of Eberbach, who wrote it in 1220, claiming that he extracted it from Hildegard’s writings. Another work erroneously attributed to Hildegard is entitled _Revelatio de fratribus quatuor mendicantium ordinum_, and is directed against the four mendicant orders--Franciscans, Dominicans, Carmelites, and Augustinians. It also has been printed, but is wholly spurious, and was probably composed towards the latter part of the thirteenth century. V. SOURCES OF HILDEGARD’S SCIENTIFIC KNOWLEDGE In the works of Hildegard we are dealing with the products of a peculiarly original intellect, and her imaginative power and mystical tendency make an exhaustive search into the origin of her ideas by no means an easy task. With her theological standpoint, as such, we are not here concerned, and unfortunately she does not herself refer to any of her sources other than the Biblical books; to have cited profane writers would indeed have involved the abandonment of her claim that her knowledge was derived by immediate inspiration from on high. Nevertheless it is possible to form some idea, on internal evidence, of the origin of many of her scientific conceptions.