DISCOVERY 



A MONTHLY POPULAR 

 JOURNAL or KNO^WLLDGE 



No. 4. APRIL 1920. 



PRICE 6d. NET. 



DISCOVERY. .\ Monthly Popular Journal of Know- 

 ledge. 



Edited by A. S. Russell, i\I.C.. D.Sc, 8 Severn Road, 

 Sheffield, to whom all Editorial Communications should be 

 addressed. 



Published by John Murray, 50A Albemarle Street, 

 London, W.i, to whom all Business Communications 

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Editorial Notes 



A CLEAR, uncoloured statement of what commercial 

 aircraft can and cannot do has been recently given by 

 Mr. Holt Thomas, and deserves attention. On the 

 whole the prevailing opinion with regard to the com- 

 mercial possibihties of aircraft is pessimistic. Yet 

 during the war it looked sometimes as though aircraft 

 were going to be everjlhing in the future. Mr. 

 Thomas's view lies between these extremes. He re- 

 cognises that in this country the aeroplane cannot 

 compete at present with existing forms of transport, 

 but it may supplement them. It can with advantage 

 carry mails, parcels, and peissengers on urgent busi- 

 ness, when part of the journey as ordinarilj' accom- 

 pUshed is over the sea. Thus an aeroplane can com- 

 pete with train and boat in a joumej' from London 

 to Paris or to Cork or DubUn, but not to Manchester 

 or Edinburgh. The aeroplane travels, of course, 

 twice as quickly as a train, but there is time lost in 

 getting to and from the aerodromes at both ends, 

 which reduces the overall speed of the journey con- 

 siderably. Moreover, trains can, and aeroplanes 

 usually do not, travel at night. In addition to all this 

 there is the weather. Fog is the great nuisance in 

 fl\ing. Wind may help or hinder speed, but fog 

 makes the pilot blind. Some kind of reliability of 

 service is necessary before the business man will trust 



his messages or himself to the aeroplane. Yet, though 

 we cannot abolish bad weather, we can partially con- 

 quer it by suitable organisation ; and this is discussed. 

 Mr. Holt Thomas thinks that pleasure flying will 

 never be very popular. It is too tedious, too unin- 

 teresting. Joy-rides in France seemed great fun. 

 Does one become blase after a bit ? It seems so. One 

 hears of owners selling their aeroplanes because fly- 

 ing bored them. 



A very interesting account of a journey in an un- 

 known part of Arabia, Southern Najd, is given by Mr. 

 Philby, of the Indian Civil Service, in the March num- 

 ber of The Geographical Journal. Mr. Philby is an 

 authority on Arabia. He is the only living European 

 who has crossed the peninsula from the Persian Gulf to 

 the Red Sea. This account does not deal with this 

 big joumej', but with an " excursion " of three hun- 

 dred miles out and three hundred home through a 

 dangerous part of the country. From surveys made 

 by Mr. Philb}- a map of this part of Arabia has been 

 made. The account of a journey made by Palgrave, 

 an Englishman, into Central Arabia in 1862 is criti- 

 cised. Part of this man's account seems to be in- 

 accurate, part purely imaginative. 



***** 



Quite recently an account has been given of a new 

 way of making soap. Clay in the " colloidal form," 

 when suitably prepared, may be satisfactorily sub- 

 stituted for a large proportion (up to about 50 per 

 cent.) of the fatty acids in soap. (Matter may roughly 

 be said to be in the " colloidal form " when it is in an 

 extremely fine state of subdivision.) As clay is 

 cheap, and soap relatively dear, the substitution of 

 clay in this form for the fatty acids produces a not- 

 able reduction in cost. The clay is a real substitute 

 for soap, and not an adulterant. Hot solutions of 

 colloidal-clay soap form jellies on cooling, and thus 

 this soap not only resembles ordinary soap in appear- 

 ance, but in cleansing properties it is said to be even 

 better than pure soap. Developments of this inter- 

 esting disco\-ery will be awaited with interest. 



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