Pagel in Puschmann's History of Medicine gives a list {320} of the books written by Albert which are concerned with the physical sciences. These were: Physica, Books VIII., that is, eight treatises on Natural Science, consisting of commentaries on Aristotle's Physics and on the underlying principles of natural philosophy, and of energy and movement; four treatises concerning the Heavens and the Earth, which contain the general principles of the movement of the heavenly bodies. Besides there is a treatise On the Nature of Places, consisting of a description of climates and natural conditions. This volume contains, according to Pagel, numerous suggestions with regard to ethnography and physiology. There is a treatise on the causes of the properties of the elements, which takes up the specific peculiarities of the elements, according to their physical and geographical relations. To which must be added two treatises on generation and corruption; six books on meteors; five books on minerals; three books on the soul, in which is considered the vital principle; a treatise on nutrition and nutritives; a treatise on the senses; another on the memory and the imagination; two books on the intellect; a treatise on sleep and waking; a treatise on youth and old age; a treatise on breath and respiration; a treatise on the motion of animals, in two books, which concerns the voluntary and involuntary movements of animals; a treatise on life and death; a treatise in six books on vegetables and plants; a treatise on breathing things. His treatise on minerals contains, according to Pagel, besides an extensive presentation of the ordinary peculiarities of minerals, a description of ninety-five different kinds of precious stones, among them the pearl, of seven metals, of salt, vitriol, alum, arsenic, marcasite, nitre, tutia, and amber. Albert's {321} volumes on the vegetables and plants were reproduced under the editorship of Meyer, the historian of botany in Germany, and published in Berlin (1867). All Albert's books are available in modern editions. In a word, there was scarcely a subject in natural science which Albert did not treat, in what would now be considered a formal serious volume, and no department of science that he did not illuminate in some way, not only by the collection of information that had previously been in existence, but also by his own observations, and especially by his interpretations of the significance of the various phenomena that had been observed. His work is especially noteworthy for its lack of dependence on authority and the straightforward way in which the great pioneer of modern science made his observations. Some of Albert's contemporaries, and especially his pupils, were almost as distinguished as he was himself in the physical sciences.