May 12. I have had a slight feverish attack for the last few days, and I feel ill, or rather I feel low-spirited. Whence come those mysterious influences which change our happiness into discouragement, and our self-confidence into diffidence? One might almost say that the air, the invisible air, is full of unknowable Forces, whose mysterious presence we have to endure. I wake up in the best of spirits, with an inclination to sing in my heart. Why? I go down by the side of the water, and suddenly, after walking a short distance, I return home wretched, as if some misfortune were awaiting me there. Why? Is it a cold shiver which, passing over my skin, has upset my nerves and given me a fit of low spirits? Is it the form of the clouds, or the tints of the sky, or the colors of the surrounding objects which are so change-able, which have troubled my thoughts as they passed before my eyes? Who can tell? Everything that surrounds us, everything that we see without looking at it, everything that we touch without knowing it, everything that we handle without feeling it, everything that we meet without clearly distinguishing it, has a rapid, surprising, and inexplicable effect upon us and upon our organs, and through them on our ideas and on our being itself. How profound that mystery of the Invisible is! We cannot fathom it with our miserable senses: our eyes are unable to perceive what is either too small or too great, too near to or too far from us; we can see neither the inhabitants of a star nor of a drop of water; our ears deceive us, for they transmit to us the vibrations of the air in sonorous notes. Our senses are fairies who work the miracle of changing that movement into noise, and by that metamorphosis give birth to music, which makes the mute agitation of nature a harmony. So with our sense of smell, which is weaker than that of a dog, and so with our sense of taste, which can scarcely distinguish the age of a wine! Oh! If we only had other organs which could work other miracles in our favor, what a number of fresh things we might discover around us! May 16. I am ill, decidedly! I was so well last month! I am feverish, horribly feverish, or rather I am in a state of feverish enervation, which makes my mind suffer as much as my body. I have without ceasing the horrible sensation of some danger threatening me, the apprehension of some coming misfortune or of approaching death, a presentiment which is no doubt, an attack of some illness still unnamed, which germinates in the flesh and in the blood. May 18. I have just come from consulting my medical man, for I can no longer get any sleep. He found that my pulse was high, my eyes dilated, my nerves highly strung, but no alarming symptoms. I must have a course of shower baths and of bromide of potassium.