Science Siftings

New Zealand Tablet, 13 November 1913, Page 51

Science Siftings

By 'Volt.'

Treatment of Precious Stones,

Under the careful treatment of a skilful ‘doctor’ a precious stone may very likely become worth ten times more than its original value. Diamonds, perhaps, have received more attention than any other gems. These are treated generally in order to rid them of a yellow tinge which greatly reduces their value. Pearls, lose their vitality and require very expert treatment.. The outer skin turns black as old age creeps upon them,, and this has to be most skilfully removed by the: doctor. Turquoises often change in color from their beautiful blue to a kind of sea-green, and they then have to be skinned and repolished. Rubies which get ‘ run down ’ improved in color and appearance by tne application of a certain vegetable dye. The ‘ patient ’ is subjected to a course of massage until the normal growth of good health is maintained. Sapphires generally have to be reduced in vitality. Their coloring has frequently to be softened down by a series of baths of liquid and sunshine.

A Strange Phenomena of the Sea.

Since Columbus discovered the Sargasso Sea the weed that at certain seasons covers leagues of it has been accounted as one of the strange phenomena of the sea. Various theories have been advanced to account for the origin of the weed. Captain Beauchant, R.N.R., states in a communication to the Imperial Merchant Service Guild that, while on a voyage from Norfolk, Virginia, to Rio de Janeiro, he got into a _ vast field of the weed, but took no special notice till the officer of the watch reported that the temperature of the water had suddenly risen from 76deg. to 80deg. Fahr. Then he noticed that round the patches of weed there floated vast numbers of red-brown berries, some of which had small shoots sprouting from them. A boat was launched, and samplies in various stages of growth were collected. From this it would seem, the captain concludes, that the month of May, with the declination of the sun about 17deg. 18min. N., is the growing season in those latitudes.

Boiling Water to Make Ice.

Water may he boiled and frozen both at the same time. The idea is a little startling, but the explanation is simple enough. The temperature at which water boils depends purely on the air pressure of its surface. If the air pressure is high the water must be made a good deal hotter to boil than is necessary at low pressure. On mountains, where the air pressure is lower than at sea level, water boils easily at low temperature.. In cooking vegetables of all kinds a certain degree of heat is required, and where water boils before that, vegetables won’t cook. Consequently, they have to be put in a closed boiler, so that the generated steam will create pressure for the water to boil beyond the required temperature. For an experimental proof of this fact the water is placed in a vessel and the air exhausted above the surface of the water. As the process of pumping goes on the water will boil violently, the steam congealing on the sides of the exhaust vessel. If the pumping is continued long enough and the outside is cooled below the freezing point of the water, the water will continue boiling and bubbling until it is a mass of ice. This fact is made use of in estimating the height of mountains. At sea level water boils at 212 degrees Fahrenheit. This principle does not apply to water alone, but to all liquids.

Palmerston North (From our own correspondent.) ■„, s . November 2. : The All Nations bazaar will be opened by his Worship the Mayor (Mr. J. A. Nash) on Monday night in the Empire Hall, and will run throughout show week. Everything is in readiness, and I trust that success will crown the efforts of the ladies in charge, and Mr. «T. O'Brien, the energetic secretary, At the meeting of the St. Vincent de Paul Society on Thursday of last week, the conference received . a very welcome visit from Mr. O'Meara, the newly-elected president of the Particular Council at Wanganui. He addressed the members, and expressed himself as being very pleased to find so many present on such an inclement night. The president (Bro. H. Oakley) thanked him for his address and his kindness in staying over night to visit the conference. The many friends of Mrs Jessie Redwood will be grieved to learn of her death on last Thursday morning. The deceased was out shopping on the previous Thursday, when she met with an accident, being knocked down by a plank which fell from a scaffolding on which painters were standing. She was severely bruised, and was taken home in a cab suffering from shock. Early on Wednesday last hemorrhage of the brain set it. She received the last rites of the Church, and passed away the following day. She leaves a husband, one son, a sister (Miss Whitaker), and two brothers (Mr. Whitaker, of Wellington, and Mr. Austin Whitaker, of Hawera), to mourn their loss. She had been a most untiring Church worker, especially in

Palmerston, where she had resided for the past fourteen years. The remains were interred in the local cemetery on Saturday, the members of St. Vincent de Paul Society acting as pall-bearers.R.l.P.