ACETAN1LID 



22 



ACETYLENE 



result will be the cost per hour. Of course two 

 men working one hour must be counted as one 

 man working two hours. 



(3) Labor of horses. The expenses of the 

 horse account will include feed, a reasonable 

 charge for space in the barn, and man-labor for 

 their care. If they are worth less at the end of 

 the year than at the beginning the difference is 

 charged to the account. A year's interest on 

 their value, and insurance and taxes on them, if 

 any, are added. The account is credited for 

 manure produced. The total cost of the horses 

 for the year divided by the number of hours of 

 work will give the cost per hour. 



(4) Machinery, equipment and harness use. 

 The cost of this account for the year is found as 

 in the case of horses by charging materials, 

 labor, interest, rent, insurance, depreciation and 

 taxes. It is important to charge adequate depre- 

 ciation, or decrease in value. The number of 

 hours by which the total is divided should not 

 include hours in which equipment was employed 

 for the benefit of other equipment, as for in- 

 stance when harness and wagon are used in 

 bringing new machinery to the farm. 



(5) Rent, hail insurance, depreciation and 

 taxes on the land used (in proportion to its fer- 

 tility), and a share of the like costs for buildings 

 and fences on the farm. C.H.H. 



ACETANILID, as et an' e lid, a highly poison- 

 ous drug, frequently given as a medicine be- 

 cause it has the effect of deadening pain. Its 

 presence in numerous headache powders and 

 tablets is a source of great danger (see HEAD- 

 ACHE). Such remedies should be avoided, as 

 large doses of acetanilid have in many in- 

 stances proved fatal. It is a white, crystalline 

 powder, and is made by treating aniline with 

 acetic acid. J.F.S. 



ACETIC ACID, a set' ic (or aseet' ic), in its 

 pure and water-free state, is a colorless liquid, 

 a little heavier than water. It has a very sharp 

 odor and a painful action upon the nose and 

 eyes. It is a caustic, that is to say, a substance 

 which acts upon the skin, producing severe 

 burns. When cooled to 62 F. (the tempera- 

 ture of a cool room), pure acetic acid solidifies 

 into ice-like crystals. For this reason pure 

 acetic acid (even when liquid) is called glacial 

 acetic acid. Dilute acetic acid, that is, acetic 

 acid mixed with water, is cheaper than the 

 glacial acid. Druggists keep solutions of six 

 and of thirty-six per strength. 



Acetic acid takes its name from the Latin 

 acetum, meaning vinegar. It is this acid to 

 which the sourness of vinegar is due. The 

 interesting process by which acetic acid is 

 formed from dilute alcohol is described under 

 the title VINEGAR. Vinegar contains only from 

 four to eight per cent of acetic acid. Concen- 

 trated acetic acid was first obtained from vine- 

 gar in the year 1700 by the German chemist 



Stahl. Today it is made commercially from 

 hardwood by distillation, being thus a by- 

 product of the manufacture of charcoal (which 

 see) and wood alcohol. The crude acid first 

 obtained is called pyroligneous acid (from the 

 Greek pur, meaning fire, and the Latin lujnum, 

 meaning wood). This crude acid is used to 

 some extent in dyeing. The greater amount, 

 however, is converted into pure dilute acetic 

 acid. 



Acetic acid is used extensively in the manu- 

 facture of white lead, acetone and the acetates. 

 Among the important acetates are those of 

 lead, calcium, sodium, copper, aluminum and 

 iron. Lead acetate is sugar of lead. Verdigris 

 is a copper acetate used in the manufacture of 

 Paris green. The acetates of sodium, alumi- 

 num and iron are used in dyeing. J.F.S. 



ACETYLENE, aset' ileen, a clear, color- 

 less gas, of great commercial importance for 

 lighting purposes. It ignites easily, and burns 

 with a bright but smoky flame. Ordinarily the 



I 



TWO TYPES OF ACETYLENE BURNER 

 gas has a peculiar odor, somewhat like that of 

 garlic, but when it is burning has no odor. 

 It was once largely used for automobile and 

 bicycle lamps, and is now much employed in 

 illuminating country houses. Acetylene gas was 

 formerly regarded as dangerous, but as a mat- 

 ter of fact it is less poisonous than ordinary 

 illuminating gas, and, if handled with reason- 

 able care, is not more likely to explode. The 

 smoke of the acetylene flame is eliminated by 

 using a special burner, constructed on the prin- 

 ciple shown in the accompanying illustration. 

 There are two small openings, from which the 

 gas issues and mingles with the air. The acety- 

 lene burners used in house-lighting consume 

 about seven-tenths of a cubic foot per hour, 

 and give a light of about twenty candle power. 

 The cost of this light is about three-fourths 

 that of ordinary illuminating gas. 



Manufacture of Acetylene Gas. The cheap- 

 ness of this gas is due chiefly to the simplicity 

 of its manufacture. Chemically it is composed 



