144 
the pupil. There was a want of sympathy with the 
learner. For example, the writers on Geography began 
with the globe, and expounded the elements of Spherical 
Trigonometry and Astronomy, talking of #erzdians, 
parallels, the tropics, the eguator, and the ecliptic. At 
present the best teachers of geography fo young children 
begin with the place where the pupil lives and dwells ; 
thence they proceed to the surrounding districts, to neigh- 
bouring countries, and end with the Globe. 
Bacon says that “wherever it is possible knowledge 
should be zmsz¢xzated into the mind of another in the 
manner in which it was first discovered.” If this prin- 
ciple were fairly carried out it would work great changes 
in our methods of teaching. 
WILLIAM RUSHTON 
Queen’s College, Cork 

MOSS LOCHS 
ANS these lochs are seldom visited save by sportsmen of 
either the rod or the gun, it will be necessary for 
me to give a short description of them. These lochs are 
generally situated high up, near the tops of the hills, 
the hills being wholly or in part covered with heather and 
moss. They are of small size, varying from about a mile 
to a hundred yards in length; the water is of a dark 
porter colour. They look asifan immense hole had been 
dug in the peat, and the hole then filled with water; the 
banks, which are wholly or in part composed of peat, rising 
almost perpendicularly out of the water, and at some places 
extending downwards for many feet under it; at other 
places going only to a depth of a foot or two, and then 
extending for some feet in a nearly horizontal direction, 
when they again dip abruptly to a considerable depth. 
These abrupt precipices of peat, as seen under the water, 
are often formed in curious, fantastic shapes, and look 
more like rock than soft peat ; and when seen by the sun- 
shine—broken by the passing waves— through the dusky 
water, with the surroundings of bleak, bare hill, total 
silence, save the plaintive cry of some bird passing over- 
head, and no life, save the lizard and the snake—the whole 
presents a scene, the weird effect of which on the imagina- 
tion is seldom if ever exceeded by anything else in nature. 
What strikes the observer of these lochs is, that not 
only are the banks made of peat, but the sides and 
bottom are wholly or in part made of the same material ; 
and there seems to be no difference between the peat at 
the bottom of the loch and that on the banks. It looks 
exactly like as if the peat had begun to be formed at the 
bottom of the loch, and had gradually extended upwards 
till it had risen above the water. Yet it could not have 
done so, because, although water-lilies and some grasses 
areseen growing under a depth of a foot or two of water, 
yet all vegetation ceases at a depth of a very few feet. 
How then came the sides and bottom of these lochs to be 
formed of peat? There are no signs of any convulsions 
of nature after the peat had been formed to account for it. 
If produced by any upheaving of the earth stopping the 
exit of the water, the upheaving must have been very 
violent, because many of these lochs are deep and yet of 
but small size, How, then, came the peat in the position 
in which we now findit? An examination of the outlet 
will at once explain the difficulty. The stream which 
leaves the loch winds its way through mossy ground, the 
bottom of its channel being covered with water plants. 
These water plants, as they grow from year to year, are 
gradually filling up the channel, and so adding to the 
depth of theloch. It is now easy to understand how peat 
is found at such depths in these lochs. We will suppose 
the loch to begin from marshy ground or from a small 
Icch. The channel of the outlet-—being covered with 
water plants—gradually gets filled up, so increasing the 
depth of the water in the lake, while vegetable life is busy 
NATURE 

[Fune 22, 1871 

adding peat to the banks. And thus marshy ground ora 
shallow loch with shelving beach is converted into a deep 
moss loch with perpendicular sides. The rising of the 
channel of the outlet and of the sides does not always 
take place at the same relative rate. In one loch recently 
visited the peat bank was about eight feet above the water, 
whilst in another where there was a vigorous growth of 
water plants in the outlet, the water was within a few inches 
of being overits banks. That water plants are capable of 
producing this result will be doubted by none who have 
seen them fairly establish themselves in a pond, how 
soon they over-run, and, if left alone, fill it up. 
Moss lochs stand in marked contrast to other lochs. In 
other lochs the water, as it passes from them, has worn 
their channels, and is year by year wearing them further, 
so lowering the water in them; whilst in moss 
lochs the channels are year by year being filled up, so 
gradually raising the water in them. It may be 
objected that the water plants in the outlet would be up- 
rooted by the water from the loch during floods; but 
such is not the case, because in most cases, when the 
water leaves the loch, it passes through a nearly level 
channel, so that it never gets up speed sufficient to damage 
its bed. And besides, these lochs being situated near the 
tops of the hills, they drain but a small extent of country. 
In no case visited had any of the lochs a stream of any 
size running into it, and the amount of water which passed 
from them was in every case small. 
As there are few rules without exceptions, it is possible 
that the rule that the outlets from moss lochs are covered 
with water plants may not hold good in every case; it is 
quite possible that the outlet from a moss loch might be 
over a rocky channel. If such should happen to be found, 
it does not necessarily prove that it was not formed in the 
way shown. The plants might continue to fill up the 
outlet till the water was raised to such a height that it 
found a passage over a new channel at a part of the hill 
where there was no moss and nothing but bare rock. We 
would thus have a moss loch grown in the way shown, 
but which had ceased to grow. 
JOHN AITKEN 


WRITERS ON SCIENCE 
fre the recent dinner of the Royal Literary Fund, Sir 
Henry Anderson proposed the toast of “ Writers on 
Science.” We make the following extracts from the reply 
by Dr. Richardson from the report of the Society :— 
“Who are the writers on science? Are they as 
well known as other great writers? They are not. 
They are less fortunate, and, therefore, the more 
worthy of the exceptional honour you would bestow on 
them. Excuse me a moment or two while I indicate the 
peculiarities of the position of the writer on science. He 
is a man communicating to the word that which is, by 
comparison, new to the world. The poet can cast 
back for his models to a time when the Greeks had not 
so much as the figment of ‘an alphabet. The theolo- 
gian may go back for his lesson to the earliest manifes- 
tations of the life of intellect on the planet. The historian 
finds subject and matter ready for his hand from the 
oldest and remotest, as well as the newest, writings and 
traditions of races and peoples. The story-teller is em- 
barrassed with the richness of the past, and troubled by 
the greed of his admirers for more of his work. These all, 
indeed, are but the continuing interpreters of things, 
events, thoughts, which every man who claims to read 
claims also to understand. The writer on science has 
none of these advantages ; he is but newly born into an 
old world of thought, and is not simply telling of new 
wonders, but is often himself learning at the same time as 
he is instructing an audience unlearned in his know- 
ledge. Thus he comes slowly into the recognised 
