Year: 1873

Waste in Steam Engines.

 This waste arises from a variety of causes list, bad firing, which means bad combustion 2nd, insufficient sur face to absorb the heat 3rd, m llnclean condition of that surface, either from internal or external deposit or both 4th, a faulty proportioning of the parts of the boiler to each other and to the work to be done, which causes heated water to be carried over with the steam "a cause of deficiency of. evaporation, which, however, so far from being as a rule detected goes to swell the apparent duty of the boiler.

 But firing may result in the fire being too thick or, too thin or irregular. If too thick the carbonic acid that is gen. erated by the combustion of the lower part of the fuel with which the air first comes in contact is changed i'll it's pas sage through the upper part of the fuel into carbonic oxide, by absorbing from the fuel second equivalent of carbon. If this gas, carbonic oxide, does not meet with free atmospheric air, and | meet with it at a suitable temperature in the upper part of the furnace, it must remain unconsumed, and will pass 

 and make its escape into the air, carry ing with it the valuable unconsumed carbon of the coal in gaseous form. It is commonly said that smoke is uneon- sumed fuel. This is true but 1t Is not commonly recollected that there may be

 invisible smoke arising (even from a

 eoke-fre) which shall contain the highly

 combustible ingredient carbOnic oxide

 gas. When it is remembered that every

 pound of coal burnt into carbonic acid

 Is capable of evaporating about 13 lb. of

 water from PIP deg, while pound of

 coal, converted only into carbonic oxide,

 is capable of evaporating but lb., 1t

 will be seen how necessary it is that no

 mismanagement of the fire should cause

 portion of the fuel thus to escape un-

 burnt up the chimney. Another defect

 in the management of fire Gan opposite

 defect, as 1t were) by which coal may be

 wasted is the admission of too much

 air and this arises when the fire is too

 thin in relation to the chimney-draft, or

 when (a more common eviD 1t Is thin in

 places, owing to the negligence of the

 firemen in keeping it properly levelled.

 The way ill which waste arises from these causes is that unnecessary air is introduced into the fire at temperature | be heated, and then (even if the heat

 be abstracted from it, as far as practi- cable by the boiler) it will escape up the chimney at temperature of from 200 deg. to 300 deg. in excess of that which

 it had and the whole of this excess re- 7 presents wasted coal. Thus, on the { one hand, it is of importance that there , should be proper amount of air to se- cure the perfect conversion of the car r bon into carbonic acid and, on the

 other hand, it is most desirable that = this amount should not be exceeded, in 9 volving the necessity of uselessly heat ) ing air not wanted for combustion K Such a happily balanced state of things

 it is almost impossible but not aboslute- r ly impossible, though only attained at v competitive trials, and when these trials : are conducted by highly skilled men. Star Drift.

 One of the most remarkable discover 1 ies supposed to be made by modern Q science is the drifting of the stars. Nr. t Richard A. Proctor, Secretary of the I Royal Astronomical Society, claims the " merit of first suggesting the possibility q of there being in fact no fixed stars but II Professor Huggins is said to have first .e demonstrated the fact that certain of the

 stars, notably Sirius, axe wandering l, through space with almost incredible n rapidity. The undulatory light-wave r. are the criteria by which this approach n. or recession is formed, and the rate a Id which they strike the eye of the ob e. server gives the proof of the stars com 10 ing toward the earth or going from it IT. If the waves come in quicker succession to than from luminous body at rest, tn I source of light, according to a well as known law, is approaching; If, on tn d. contrary, they come in slower sue i'd cession than from luminous body 6 70 rest, the source of light is recedine to Not only does this " star drift---as MI

 Proctor calls h---take place with singl D. stars, but whole groups, with rythmi 1- motion, are circling among themselves SO sometimes drifting silently, swiftl. ,z- mysteriously, in a common direction he sometimes intervolved in manner { ,d present unaccountable.

 be

 There are in Austria twelve priso lis for men and six for women. The nun ut Der of prisoners at the end of last yei ed was 10, 422 of both sexes. The numb' ffi- of persons who died in prison. dRNn

 the year was 552. Every prisoner je obliged to attend school regularly, a1 oh popular lectures are delivered to u

 prisoners on Sundays and holidays.