All science and all art may be divided into that which is subservient to life, and which is the object of it. As subservient to life, or practical, their results are, in the common sense of the word, useful. As the object of life or theoretic, they are, in the common sense, useless; and yet the step between practical and theoretic science is the step between the miner and the geologist, the apothecary and the chemist; and the step between practical and theoretic art is that between the bricklayer and the architect, between the plumber and the artist, and this is a step allowed on all hands to be from less to greater; so that the so-called useless part of each profession does by the authoritative and right instinct of mankind assume the superior and more noble place, even though books be sometimes written, and that by writers of no ordinary mind, which assume that a chemist is rewarded for the years of toil which have traced the greater part of the combinations of matter to their ultimate atoms, by discovering a cheap way of refining sugar, and date the eminence of the philosopher, whose life has been spent in the investigation of the laws of light, from the time of his inventing an improvement in spectacles. But the common consent of men proves and accepts the proposition, that whatever part of any pursuit ministers to the bodily comforts, and admits of material uses, is ignoble, and whatsoever part is addressed to the mind only, is noble; and that geology does better in reclothing dry bones and revealing lost creations, than in tracing veins of lead and beds of iron; astronomy better in opening to us the houses of heaven than in teaching navigation; botany better in displaying structure than in expressing juices; surgery better in investigating organization than in setting limbs; only it is ordained that, for our encouragement, every step we make in the more exalted range of science adds something also to its practical applicabilities; that all the great phenomena of nature, the knowledge of which is desired by the angels only, by us partly, as it reveals to farther vision the being and the glory of Him in whom they rejoice and we live, dispense yet such kind influences and so much of material blessing as to be joyfully felt by all inferior creatures, and to be desired by them with such single desire as the imperfection of their nature may admit;[5] that the strong torrents which, in their own gladness fill the hills with hollow thunder and the vales with winding light, have yet their bounden charge of field to feed and barge to bear; that the fierce flames to which the Alp owes its upheaval and the volcano its terror, temper for us the metal vein and quickening spring; and that for our incitement, I say not our reward, for knowledge is its own reward, herbs have their healing, stones their preciousness, and stars their times. Sec. 9. Their relative dignities.