Scientific and Useful.

Lake Wakatip Mail, Issue 1579, 4 March 1887, Page 4

Scientific and Useful.

LAKES I* NORWAY. Many of the lakes of Norway are excavated far helo*v the level of tho sea. In thi« re«peot they resemble the Italian lakes. Two Norwegian lakea have their lowest depths more than a thoaand feet below the sea level. I THB LIGHTING OF THB GBKAT STATTTB OP LIBERTY. The electric illumir ation of BartV od s statue ol Liberty has not proved so sucoe-sful , ■a was anticipated. The lighting of the torct | was pronounced successful. Held high above | the s'atue's head, the light from the torch ] made a brillimt beacon for the entire harbour ] and wa* plainly visible for many mi'es at sea. ( The arm holding the torch was in sbndow, | and at the distance of a mile the statue itself j was invisible. It is intended to remedy this < bv a different arrangement of the arc lights j placed at the ba*e. Seen from Brooklyn , Bridge, the light of the torch was brilliant, j but only the pedestal and uplifted arm were . visible. 1 SWEETESBD MOBTAB. ' Mr Thomson Hankey points out that cano sugar and lime form a definite chemical compound, which has very strong binding qualities, and form a cement of exceptional •treng'h. Equal quantities of finely powdered lime of a common kind and of good brown sugar, mixed with water, form a mortar which ha» been found to jjin stones and even glass with great success, It is important that the lime chould he thoroughly air-eUked, for if any dry particles be left they will swell an 1 eventually break the joint. It is stated that this mortar is equal in strength to Portland cement, and that the latter may probably be improved by the addition of sugar, or perhaps even of treacle. A number of small experiments which have been made have proved entirely successful, an 1 it now remains to see whether the material offers advantages in actual work sufficient to pay for its extra cost. A MOSSTEB ELECTRIC CLOCK. The Standard Electric Time Company, of New York, has been engaged for somo time past in preparing the mechanism, &c., for tho largest clock in the world, one having a face 25ft. in diameter. This clock i 9 to be put against the wall of a bui.ding at the oruer of Twenty-third Street and Fifth Av.nue, resting on a lower building at the junction of the thoroughfares. The works are composed of 16 pairs of eltctro-mngrets placed around a 6in. gear wheel. At the face of each pair of magnets is placed an armature exi ending to the gear wheel. Kvery second the current from the main line into circut 01 c«-ll« of a local battery, energ. ijing one pair of magnets and starting the wheel, the impulse then affecting each pair in rotation, and distributing the pull or load very evenly. The dial is painted on the wall of the building, and the hands travel around in front of it as in the ordinary clock. This i gigantic clock is intended to serve as an advertisement. 13 jrrilEß SELF-LUMINOUS ? Mr A. B. Biggs (Tasmania)) finds, from careful experiment, that the surface of Jupiter is very mueh brighter than it should be on the supposition that he only r. fleets light to us received from 'he sun. As compared with Mars, he makes Jupiter's surface brightness to be 22 tinus as great as it ought to be, and as compare.! with the moon 12 7 times. These comparisons go on the assumption that the surfaces to be compared are equally reflective—that is of equal whiteness. That they are really not so, may be considered as certain. Bui even supposing Jupiter's surface to be of the whiteness of snow, we have at the poles of Mars planetary snow with which to compire it, and illuminated with twelve times the intensity of Jupiter's sunshine. As compared with the moon, the vaporous envelope of Jupiter (whatever its nature) is piobably more reflective than the bare and broken lunar surface. There musf, however, remain a vast amount of illumiuation to be accounted for in some other way. Mr Biggs accounts for it by assuming that Jupiter is self-luminous like the sun, but, of course, in a much less degree, lie has not yet, on account of his grea' size, cooled down to the dark conditions of the earth, the moon, and Mars. AN OBTBICH BACK. I reminded the doctor of a promise he had made me to show me a foot race between ostriches. We immediately went to a broad open space between the ostrich pens and the house.. One of the keepers opened the door of one of the pen', and in rcsponce to the doctor's call two superb ostriches came running to him. After caressing the gentle creatures for a few moments he Bhowed them . a handful of figs, of which they are exceedingly Lnd. Two of his men then retained the birds by placing nooses abjut their legs until he and myself had walked away about a quarter of a mile. Then, at a signal from the doctor, the birds were released and the race begun. It was a rare sight. Ornithologists tell us that the stride of the ostrich when feeding is from 20 to 22 inches; when walking, but Lot feeding, 26 inches; and when terrified, from 11} to 14 feet. It seemed to me that in this race for a hund'ul of figs from their master the gigantic birds covered the last-named distance at every stride. Like the wind they came, their great necks stretched forward and upward to their utmost length, and their wings working. They kept well abreast for nearly half the distauce, and then one began to forge ahead. He increased his lead till within a short distance of us, when he turned his head, and seeing that his competitor was considerably in the rear, he slackened his pace, and jogging up to the doctor, received Ins reward in figs and caresses. —New York Sun. BOY INVBKTOBS. There are a good many useful inventions which are the outcome ot some boy genius, and the records of the Patent Office show that quite a nunber of patents have been issued to minors through their guardians. The invention of a valve to a steam engine is said to have been made by a mere boy. The story runs that Newcomen's engine was in a rery incomplete condition, from the fact that there was no w«y to open and ckse the valve except by means of levers operated by band. He sent up a large engine at one of the mines, and a boy (Humphrey l'otter) was hired to work these levers. Although ibis is not hard work, yet it required bis constant attention. As he was working the levers, he saw that parts of the engine moved in the right direction and at the same time he had to open and close the valves. H« procured a strong cord, and made one end fast to to the proper part of the engine, and the other end to the valve lever, and the boy had the satisfaction of seeing the engine move with per.'ect regularity of motion. A short time I after the foreman came around, and saw the 1 boy playing marbles at the door. Looking at the engine he saw the ingenuity of the boy, ' and also th 6 advantage of his inveution. The ' idea suggested by the boy'i inventive genius wis pat in a practical form, and made tb Q i (team engine an automatically working maehint.