410 



NATURE 



[March 6, 1879 



towards the sheep field. What taught him that he could thus 

 reach his game unobserved ? A. J. A. 



Here is an instance of "instinct" which shows, I think, that 

 there is no difference whatever between the reason of animals 

 and that of men. 



A mare here had her first foal when she was ten or twelve 

 years old. She was blind of one eye. The result was that she 

 frequently trod upon the foal, or knocked it over when it hap- 

 pened to be on the blind side of her, in consequence of which 

 the foal died when it was three or four weeks old. The next 

 year she had another foal ; and we fully expected that the result 

 would be the same. But no ; from the day it was born she never 

 moved in the stall without looking round to see where the foal 

 was, and she never trod upon it or injured it in any way. You 

 see that reason did not teach her that she was killing her 

 first foal ; her care for the second was the result of memory, 

 imagination, and thought, after the foal was dead and before 

 the next one was born. The only difference that I can see 

 between the reasoning powers of men and of animals, is that the 

 latter is applied only to the very limited sphere of providing for 

 their bodily wants, whereas that of men embraces a vast amount 

 of other objects besides this. 



The above limitation does not, I think, apply strictly to 

 domestic animals, dogs especially, which seem to acquire some 

 perceptions beyond mere animal ones. 



Hull, February 28 C. W. Strickland 



Parhelia 



Allow me to record the occurrence of parhelia here this 

 morning. ITie phenomenon lasted about twenty minutes, and was 

 fairly brilliant. No halo was apparent, merely a mock sun on 

 either side of the true one, and the line passing through the three, 

 dipped towards the south at an inclination of 2° to 3° to the 

 horizon. E. W. Pringle 



Uxbridge, March 4 



Unscientific Art 



As a specimen of Unscientific Art, let me bring to the notice 

 of yoiur readers a two-page engraving in the last number of the 

 Illustrated London Alert's, entitled "Capture of Sirayo's Strong- 

 hold." 



If there is any truth in the laws of perspective the Zulus flying 

 before the cavalry are indeed " sons of Anak." 



Scientific Club, March 2 E. W. Pringle 



Bees' Stings 



In Nature, vol. xix, p. 385, a correspondent asks whether 

 the identity of bee-poison with formic acid has yet been deter- 

 mined. Some sixteen years ago I made a few experiments with 

 the poison from wasp-stings, and found, to my astonishment, 

 that it was invariably alkaline instead of acid. A living wasp, 

 duly held in the cavity of a perforated cork, was easily induced 

 to sting a piece of turmeric paper ; a brown-red spot immediately 

 appeared. A. H. Church 



Cirencester, March i 



A NEW PROCESS IN METALLURGY^ 



LONG before human art acquired the knowledge of 

 metal-making, prehistoric man had learned to make 

 fire of the dry stems and branches of trees; in the 

 charred fragments of half -burnt wood we recognise a 

 form of carbon, the first simple elementary body produced 

 by man from the complex natural bodies with which he 

 •was surrounded. In the knowledge of the use of fire, 

 then, was the first dawn of art, particularly of that art 

 which deals with the reduction of simple bodies from 

 compound minerals. To convert metallic compounds into 

 metallic elements is the domain of the metallurgist, and 

 the means by which this is effected constitute the basis of 

 metallurgic art. Carbon was thus a necessity to metal- 

 lurgy—with the knowledge of fire the world emerged from 



' A paper with full detaiU of the process was read by John Hollway at the 

 Society of Arts on February 12, 1879; Prof. H. E. Roscoe, F.R.S., in the 

 chair. 



the stone age. From those early times down to the 

 present day, no fusion has been effected without using 

 carbon, which in the form of wood, coal, or charcoal, has 

 been the substance invariably used by the metallurgist for 

 the production of heat, and to enable him to decompose 

 and to smelt metal-bearing materials. 



The new process, however, we are about to describe, 

 has for its object the smelting of metaUiferous substances 

 without the employment of carbonaceous fuel. The 

 sulphides of iron, lead, and zinc are known to be combus- 

 tible substances of almost universal occurrence, and when 

 burnt under favourable conditions give rise to a great 

 evolution of heat. We have calculated the relative tem- 

 peratures thus produced, from which it appears that the 

 temperature at which iron p>Tites (bisulphide of iron) burns 

 in air under the conditions most favourable to the develop- 

 ment of a high temperature is over 2,000" C, protosulphide 

 of iron burning at about 2,225° C. Zinc sulphide, or blende, 

 gives a temperature of 1,992° C, and galena 1,863° C. ; 

 while calculations made in a similar manner with coal, 

 assuming it to be completely burnt, show the temperature 

 attainable to be 2,787° C. These mineral sulphides, which 

 are therefore natural and almost inexhaustible sources of 

 heat and energy, can under certain circumstances be 

 burnt more economically than their heat-giving equivalent 

 of coal. 



The best means, however, of utilising this heat-pro- 

 ducing property of metallic sulphides is not so apparent 

 as would appear at first sight. Only iron pyrites is suffi- 

 ciently combustible at a low temperature to burn in the 

 open air, the mass being raised to the temperature at 

 which the oxidation takes place solely by the union of the 

 sulphur and iron with aerial oxygen. In Spain this is 

 carried on in vast heaps of hundreds of thousands of tons, 

 and the operation extends over many months. The oxide 

 of iron that remains is typical of those mineral substances 

 which, once burned in the primeval operations of nature, 

 gave up their stores of heat and force, and became, as it 

 were, inert bodies. 



Going back now to the combustion of carbon, it is well 

 known that it bums at widely varying temperatures, as, 

 for example, in our bodies, in a common coal fire, or in a 

 powerful furnace. A great deal of attention and thought 

 has been spent upon the subject of the economy of car- 

 bonaceous fuel, and g^reat advances have been made in 

 this direction, yet the expenditure of coal or coke 

 necessary, say, to melt a given quantity of metal, still far 

 exceeds the theoretical limit. The main causes of this 

 discrepancy may be accounted for as follows : — (i) That 

 only a fractional part of the oxygen of the air passed 

 into the furnace acts upon the material to be burnt. 

 (2) That the oxygen is not brought in contact with the 

 combustible matter with sufficient rapidity to attain the 

 necessary temperature for the operation. (3) That gases 

 pass off hot and unburnt ; these are now, however, fre- 

 quently utilised. 



There is one metallurgical operation in which the first 

 two sources of loss are perfectly avoided — namely, by 

 blowing air through molten crude iron, as in the Bessemer 

 operation, where, by the burning of small quantities of 

 carbon and silicon contained in the crude iron a very high 

 temperature is attained, which is not the case in the pro- 

 cess of puddUng, where the oxidation is spread over a con- 

 siderableperiodof time,although the same constituents are 

 frequently burnt in similar proportions. But even in the 

 Bessemer process the carbon is only half burned, and a 

 large amount of heat escapes with the carbonic oxide and 

 nitrogen. When, however, we blow thin streams of air 

 through molten sulphide of iron lying upon a tuyere 

 hearth, a high temperature is produced by the perfect 

 combustion which ensues in the midst of the sulphides, 

 and no unburnt gases excepting sulphur vapour escape 

 from the surface of the molten mass. Hot nitrogen 

 and sulphurous acid being the only gaseous prodxicts 



