The poet says: "An undevout astronomer is mad," and he says truth. It is only those who know a little of nature, who fancy that they know much. I have heard a young man say, after hearing a few popular chemical lectures, and seeing a few bottle and squirt experiments: Oh, water--water is only oxygen and hydrogen!--as if he knew all about it. While the true chemist would smile sadly enough at the youth's hasty conceit, and say in his heart: "Well, he is a lucky fellow. If he knows all about it, it is more than I do. I don't know what oxygen IS, or hydrogen, either. I don't even know whether there are any such things at all. I see certain effects in my experiments which I must attribute to some cause, and I call that cause oxygen, because I must call it something; and other effects which I must attribute to another cause, and I call that hydrogen. But as for oxygen, I don't know whether it really exists. I think it very possible that it is only an effect of something else--another form of a something, which seems to make phosphorus, iodine, bromine, and certain other substances: and as for hydrogen--I know as little about it. I don't know but what all the metals, gold, silver, iron, tin, sodium, potassium, and so forth, are not different forms of hydrogen, or of something else which is the parent of hydrogen. In fact, I know but very little about the matter; except this, that I do know very little; and that the more I experiment, and the more I analyse, the more unexpected puzzles and wonders I find, and the more I expect to find till my dying day. True, I know a vast number of facts and laws, thank God; and some very useful ones among them: but as to the ultimate and first causes of those facts and laws, I know no more than the shepherd-boy outside; and can say no more than he does, when he reads in the Psalms at school: "I, and all around me, are fearfully and wonderfully made; marvellous are Thy works, and that my soul knoweth right well." And so, my friends, though I have seemed to talk to you of great matters this night; of the making and the destruction of world after world: yet what does all I have said come to? I have not got one step beyond what the old Psalmist learnt amid the earthquakes and volcanoes of the pastures and the forests of Palestine, three thousand years ago. I have not added to his words; I have only given you new facts to prove that he had exhausted the moral lesson of the subject, when he said: These all wait upon thee, that thou mayest give them their meat in due season. Thou givest, and they gather: thou openest thy hand, and they are filled with good. Thou hidest thy face, they are troubled; thou takest away their breath; they die and return to their dust. Thou sendest forth thy spirit, they are created; and thou renewest the face of the earth. But--The glory of the Lord shall endure for ever. The Lord shall rejoice in his works. Amen. HOW TO STUDY NATURAL HISTORY {290}