RANDOM NOTES

Dominion, Volume 33, Issue 141, 9 March 1940, Page 10

RANDOM NOTES

Sidelights On Current Events (By Kickshaws.) If we understand the situation, Sweden’s position is ire or iron ore. * * * Au invisible man on the films, it seems, was paid only to breathe. The resultant picture, we are in a position to state, was breath-taking. * * * It is revealed that G-Men are also responsible for the protection of wild birds. This applies especially to elusive American night-birds, we are informed. A reader has asked for the quotation used by His Majesty the King in his' Christmas broadcast. Here it is, as written by Miss M. L. Haskins, in “The Desert” : —“I said to the man who stood at the gate of the year, ‘Give me a light that I may tread safely’ into the unknown.’ And he replied, ‘Go out into the darkness and put your hand into the hand of God. That shall be to you better than light aud safer than a known way.’ ” The recent plea not to eliminate the higher grades of motor spirit as used in modern cars makes significant reading in contrast with the news that Australia intends to increase the production of alcohol fuel. The modern car will not run properly on low-grade fuel, and it will not run at all on alcohol. Yet all these fuels are suitable for use in internal-combustion engines. It is a question of design. Where the highest power is required from the smallest power unit, high-grade modern petrols are second to none. Modern high-grade fuels enable a tiny engine of extremely light weight to develop prodigious horsepower. An engine as used in a baby car has been “hotted up” by suitable design to develop over 150 horsepower instead of the usual 20 horsepower. Where light weight with high performance is required, high-grade fuels are essential. These performances are required in the air, which takes precedence of all other fuel demands, and few of us would grudge it.

There are roughly three grades of aviation fuel in use today, 100 octane, 87 octane, and 77 octane. The higher the octane number the more specialized the fuel, and the greater the power that a suitable engine of given size can develop from it. The Germans are using 87 octane fuel for their aeroplanes. The British use 100 octane. The standard commercial aviation fuel is 87 octane. Some idea of the difference in power obtained using 100 octane and 87 octane in suitablydesigned engines of exactly the same cylinder capacity makes it possible to appreciate the importance of obtaining the very best fuel for Allied aeroplanes. If 87 octane petrol is used, the engine, let us say, develops 500 horsepower under the most suitable conditions of design. A similar engine designed to use 100 octane would develop 650 horsepower. If the 77 grade were used the horsepower would fall to 400. Indeed, if a standard quality motor fuel were used the output would fall to 250 horsepower. It is, therefore, obvious that the best fuel makes a tremendous difference in the output of an aeroplane engine.

The result of using a low-grade petrol for aviation purposes is to reduce the top speed of the aeroplane. Let us consider a British machine with a maximum speed of 315 miles an hour on 100 octane fuel. If that identical aeroplane were presented to the German authorities they would have available petrol of 87 octane value. After making the necessary alterations in .design to enable this quality of petrol to develop maximum power in the same engine in the same aeroplane, the top speed would fall to 300 miles an hour —a matter of life and death to a pilot under some circumstances. High quality fuels are produced by the introduction into suitable petrol of certain chemicals called Iso-octane. This special ingredient is found in fuel supplies almost exclusively from American sources. Germany has a supply quite inadequate for her purpose. Moreover, the alcohol fuels she uses cannot be made to give equivalent results, owing to increased engine weight It is, therefore, particularly significant that at this early stage in the war Germany’s much-vaunted Air Armada uses a comparatively low-grade aviation fuel.

There are all manner of fuels available for use in internal-combustion engines, but the highest grade aviation fuel will enable the highest power to be developed from any given engine. Some of the available fuels include petrols, hydrogen gas, coal gas and alcohol. If we assume that a givensized engine develops 100 horsepower when using petrol, it is possible to discover what may be expected under the best conditions for a similar engine suitably designed to work on other fuel. If hydrogen were used the power output would fall to So horsepower. Coal gas would produce only 75 horse-power and producer gas about the same output. When alcohol fuel is used a suitably-designed engine of the same size would produce 150 horsepower. This is a significant fact. It is offset, however, by the fact that the extra weight required in the engine design goes up so fast that the power per horsepower per lb. exceeds that of the petrol unit. For aviation purposes, therefore, power alcohol cannot compete with the highest quality petrols. Somewhat similar factors arise when crude oil is pressed into service.

"I am writing to get your decision on a question which has well-nigh caused a riot here,” says “E..T.G.” "We have decided to abide by your answer. I trust you will be kind enough to give it. It is on the old question, who’s photo is a man looking at when he says, ’Sisters and brothers I have none,’ etc. You know the question? There are 36 people who say he is looking at himself, and I am one of three who holds that it is his son’s photograph. I am beginning to wonder if there is anything wrong with my mentality.” [The problem runs, “Brothers and sisters have I none, but that man’s father is my father’s son.” The best way to approach a sane decision with this apparently ever-popular cause of riots is as follows:—As the man has no brothers or sisters, he must be an only son. Under those circumstances, "my father's son” can be none other than the man himself. One can,. therefore, replace "my father's son’ with the word “myself.” The saying, therefore, is reduced to the simple one of “Brothers and sisters have I none, but that man’s father is ‘myself.’ ”.If the man be looking at a photograph when he says, “That man’s father is myself,’ he must be the father of the man in the picture. The man in the picture is, therefore, his son. It is suggested that the 3G people mentioned cut this out and keep it in case of further riots.]

“May I make use of your popular column?” says “E..T.M.” “You will be able to settle this argument. What was the total attendance at the Dunedin Exhibition? Thanking and wishing your column a long life.’ (3,200,455. J