192 THE NATURAL HISTORY 



could not be persuaded but that he was mocked by some 

 boy ; but, repeating his trials in several languages, and 

 finding his respondent to be a very adroit polyglot, he then 

 discerned the deception. 



This echo in an evening, before rural noises cease, 

 would repeat ten syllables most articulately and distinctly, 

 especially if quick dactyls were chosen. The last syllables of 



"Tityre, tu patulae recubans " 



were as audibly and intelligibly returned as the first : and 

 there is no doubt, could trial have been made, but that at 

 midnight, when the air is very elastic, and a dead stillness 

 prevails, one or two syllables more might have been 

 obtained ; but the distance rendered so late an experiment 

 very inconvenient. 



Quick dactyls, we observed, succeeded best ; for when 

 we came to try its powers in slow, heavy, embarrassed 

 spondees of the same number of syllables, 



" Monstrum horrendum, informe, ingens - - -" 



we could perceive a return but of four or five. 



All echoes have some one place to which they are 

 returned stronger and more distinct than to any other ; 

 and that is always the place that lies at right angles with 

 the object of repercussion, and is not too near, nor too far 

 off. Buildings, or naked rocks, re-echo much more arti- 

 culately than hanging wood or vales ; because in the latter 

 the voice is as it were entangled, and embarrassed in the 

 covert, and weakened in the rebound. 



The true object of this echo, as we found by various 

 experiments, is the stone-built, tiled hop-kiln in Galley- 

 Lane, which measures in front 40 feet, and from the 

 ground to the eaves 12 feet. The true centrum phonicum^ 

 or just distance, is one particular spot in the King's-field, 

 in the path to Nore-hill, on the very brink of the steep 

 balk above the hollow cart way. In this case there is no 

 choice of distance ; but the path, by mere contingency, 

 happens to be the lucky, the identical spot, because the 

 ground rises or falls so immediately, if the speaker either 



