off the view of everything more than about 500 feet below; at the same time an exclamation from a tourist caused me to look up, and I saw to my surprise a dense mass

of cloud wildly circling in the air above our heads; another moment, and it had descended upon us, and we were at once in almost total darkness.

MONG popular epidemics it would be unpardonable to omit the Aquarium mania, which reached its height about the time when many of our readers had proceeded no further than the initial A, and were as yet in happy ignorance of the

remainder of the word. The attack was general, being most severe in towns and cities; and not a few young ladies and gentlemen "felt bad," as our American cousins phrase it. The consumption of glass was alarmingly great, and it is a wonder the price was not permanently raised. Rough plate, smooth plate, bell glasses, show glasses, milk pans, basins, -in short, everything that could be used as a tank or made into one, was seized upon, and converted into an aquatic Noah's ark, for the edification and amazement of admiring friends. There was grand messing, spilling, and slopping, though, behind the scenes; tanks would leak, in spite of white-lead, red-lead, and Portland cement; bowls would capsize and saturate the carpet with a compound of dark-coloured mud,

spasmodic beetles, slimy weeds, gasping fishes, and convoluted worms; while the inhabitants of vessels which escaped such catastrophes set peace principles at open defiance, as if determined to afford a practical commentary on the poet's lines,—

"The pond's a mirror'd world, where strong on weak,

Cunning on simple, prey."

Thus many a "'weak fish and "simple" tadpole reached (if we may so say) Ponder's End by a route quite different from the Eastern Counties Railway.

In this and other ways-not to omit the bursting of vessels in frosty weather, so graphically sketched by John Leech in a former number of Punch-the aquarium mania received a check which threatened to prove a checkmate. Tanks were banished to sculleries, dark cup. boards, and outhouses; and bell glasses were turned to purely horticultural uses. But among a comparatively select few a different effect had been produced. They had learned, after many failures and discouragements, that it was quite

and its contents in a condition of tolerably uniform prosperity, and that under such circumstances there was an abundance of instruction and amusement to be extracted from them. And so it has come to pass that now most aquarium keepers take a genuine interest in their bowls or tanks, and are in thorough sympathy with the little world of life which each vessel contains.

Presuming that some of our readers desire to reap the benefit of the practical experience which has been gained during the last fourteen or sixteen years, we purpose to devote a page to sundry jottings that may be helpful "to persons about to" up a fresh-water aquarium.

set

A "pond in a parlour" is dependent for its purity, and its inhabitants for their life and health, upon certain conditions, easily explained. In nature, standing water may, as every one knows, be perfectly sweet and drinkable; but if so, its condition is due to a balance of animal and vegetable life. The duck weed which covers the surface of a pond, the reeds and rushes which fringe its margin, and the floating vegetation. which is suspended in its waters, combine to prove a powerful agency for the production of oxygen gasor "vital air," as it was formerly called; and when the sun shines, this gas is freely given off by the plants, which it studs with innumerable bubbles. On the other hand, every animal-fish, insect, worm, or whatever it may be-exerts an exactly opposite influence, breathing out carbonic acid (carbon + oxygen) gas into the water. A process of exchange, of the highest importance

the influence of sunlight the carbonic acid is absorbed by the plant, which retains the carbon, and returns the oxygen. The latter is at once breathed in or respired by the animals, to be breathed out or expired as carbonic acid. It is plain that where this wonderful "balance" is true, animals and plants will alike be maintained in a living and healthy condition; and the object of the aquarium keeper should be to attain and then to maintain this desirable equality.

It is equally plain that a globe of gold fish is no aquarium at all; and when it is also remembered that in the latter we are seeking to imitate nature as closely as possible, it will be seen that the position of a globe on a round table, in front of a window through which the sunshine pours uninterruptedly, is anything but a natural one. If we have fish in an aquarium, we must neither starve, nor boil, nor dazzle them after any such fashion. If we are able to afford a square or oblong tank, one side and both ends should be of slate, not glass; and if a glass vessel (such as an inverted bell glass) is chosen, it should be placed in a somewhat shady place, or, by means of green paper pasted on the glass, shelter should be afforded from the direct rays of the sun.

A layer of clean river sand is placed at the bottom of the aquarium, and on this small pebbles should be spread to a depth of a full inch at least. If rock work is introduced, much care is needed to avoid outraging good taste by the introduction of unnatural scenery. To make a subaqueous grotto of bright minerals