Rooting of Cuttings 



simply for indole-butyric acid. The y in this word is short, 

 like i in pin — not like y in why ; and the a of indole is always 

 short, as in doll. The other substance is derived from naph- 

 thalene, and is known as a-naphthyl-acetic acid (alpha- 

 naphthyl-acetic acid, the y this time being long, as in why). 

 There is also a beta-naphthyl-acetic acid on the market. 

 The beta acid is distinctly less useful for most horticultural 

 purposes, so if you decide to obtain a naphthyl-acetic acid for 

 ordinary gardening purposes, you should specify alpha- 

 naphthyl-acetic acid (or, alphd-naphthalene-acetic acid), not, 

 for the present, omitting the alpha part of the name. 



All these substances are very expensive, as judged by 

 ordinary standards, and the indole compounds, at least, seem 

 likely to remain expensive for a long time ; no cheap method 

 of producing them is in sight. Indole, which may be regarded 

 as the parent of the indole-acetic (indolyl-acetic) group of 

 substances, is used in small quantities by perfumers, and 

 during the Great War it attained the price of ;^ioo ($500) per 

 pound. This seemed to me to be a record for a commercial 

 chemical. Indole, however, is not a material likely to be 

 bought by the general public even at its present reduced 

 price; yet, until a short while ago; indole-acetic acid was on 

 general sale at a price of about ;^220 ($1,100) per pound. It is 

 not very much below that price now, and indole-butyric acid 

 is even dearer. 



You may think that at such prices the artificial growth- 

 substances are impossibly beyond our reach, and, indeed, 

 you will see that such prices make chemicals worth literally 

 more than their weight in gold. However, you do not need 

 more than minute quantities, and, since nobody expects to 

 sell indole-acetic acid by the pound, the usual commercial 

 unit of weight for retail sale is the gram : this is a metric unit 

 equal to about a thirtieth of an ounce. 



Current prices for some of the better-known pure sub- 

 s .mces are given on next page from the comprehensive price- 

 lisi" of the British Drug Houses Limited, of Graham Street, 

 C'i 7 Road, London, N.I : ^.^^ 



LIEi^^ARYJ at 



