HOOK. 589 



where it feasts upon the earth-worms that usually come to the 

 surface under night. Often too you may find it in the streets 

 of the populous city, carefully searching for whatever is ap- 

 plicable to its wants among the garbage that waits the sca- 

 venger's cart. 



It is pleasant and profitable to vary one's habits at times ; 

 for a naturalist in particular it were absurd to be fettered by 

 resolutions as to the precise moment of sleeping or eating. 

 Had I not once made an excursion at an unusual time of 

 day, I should not have known that Rooks are early risers. 

 The occasion was this : one night in June I had been reading 

 of volcanoes and earthquakes, and had protracted my studies 

 to an early hour. Just as I had fallen asleep, I was aw^akened 

 by a loud noise, similar at its commencement to the report of 

 a gun, but lengthened out into a series of undulatory sounds 

 resembling thunder. I rose, and looking out of the w^indow, 

 could perceive no indications of electric explosions in the clear 

 sky. A light mist lay over the town, and the air was so calm 

 that not a leaf of the poplars stirred. Again another explosion, 

 and I marvelled, listened and looked, but in vain. He who 

 listens eagerly in the silence of a calm night hears many myste- 

 rious sounds swelling and dying away at intervals. To divine 

 the cause of these I put on my clothes, w^ent out by the garden 

 door, forded the Water of Leith, and betook me to the Calton 

 Hill. 



The Hedge-sparrow and the White-throat were singing in the 

 bushes before two ; and, as I proceeded, some Thrushes and 

 Blackbirds commenced their morning hymn, at first drowsily, 

 and with few and unmusical notes. A w^atchman near Bride- 

 well informed me that a shot or tw^o had been fired, probably 

 by boys. From the hill I could perceive no symptoms of 

 thunder on the horizon, but the barking of a dog in the direc- 

 tion of Prince's Street came rattling back from the Abbey at 

 such a rate, that I easily understood how the report of a pistol 

 in so quiet a morning might be magnified into the semblance of 

 an electric explosion. The voice of the watchman was more 

 than stentorian. The sea, which was smooth as glass, and 

 could not have formed a ripple on the beach of the height of a 



