218 
THE NATURAL HISTORY 
[LETT. 
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 liorrenclum, 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 articulately 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 source of this echo, as we found by various experi- 
ments, is the stone-built, tiled hop-kiln in Gally-lane, which 
measures in front 40 feet, and from the ground to the eaves 12 
feet. The true cmtrim. plionicum, or just distance, is one par- 
ticular spot in the Kings'-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 
retires or advances, that his mouth would at once be above or 
below the object. 
We measured this polysyllabical echo with great exactness, 
and found the distance to fall very short of Dr. Plot's rule for 
distinct articulation : for the Doctor, in his history of Oxford- 
shire, allows 120 feet for the return of each syllable distinctly : 
hence this echo, which gives ten distinct syllables, ought to 
measure 400 yards, or 120 feet to each syllable; whereas our 
^ A iJionster grim, tremendous, vast and high." 
(Dry pen's ^'irg. yEn. iii. (i58.) 
