686 LILIACE^. 



Mossel Bay, and the highest, lid., at Swellendam. The drug is shipped 

 from Cape Town, Mossel Bay and Algoa Bay. 



5. Natal Aloes — Aloes is also imported from Natal, and since 1870 

 in considerable quantity. Most of it is of an hepatic kind and com- 

 pletely unlike the ordinary Cape aloes, inasmuch as it is of a greyish- 

 brown and very opaque. Moreover it contains a crystalline principle 

 which has been found in no other sort of aloes. 



The drug is manufactured in the upper districts of Natal, between 

 Pietermaritzburg and the Quathlamba mountains, especially in the 

 Umvoti and Mooi River Counties, at an elevation of 2000 to 4000 feet 

 above the sea. The plant used is a large aloe which has not yet been 

 botanically identified. The people who make the drug are British and 

 Dutch settlers, employing Kaffir labourers. The process is not very 

 different from that followed in making Cape aloes, but is conducted with 

 more intelligence. The leaves are cut obliquely into slices, and allowed 

 to exude their juice in the hot sunshine. The juice is then boiled down 

 in iron pots, some care being taken to prevent burning, by stirring the 

 liquid as it becomes thick. The drug while still hot, is poured into 

 wooden cases, in which it is shipped to Europe.^ The exports from the 

 colony have been as follows : — ^ 



1868 1869 1870 1871 1872 

 none 38 cwt. G46 cwt. 372 cwt. 501 cwt. 



Chemical Composition — All kinds of aloes have an odour of the 

 same character and a bitter disagreeable taste. The odour which is 

 often not unpleasant, especially in Socotrine aloes, is due to a volatile 

 oil, which the drug contains only in minute proportion. T. and H. 

 Smith of Edinburgh, who contributed a specimen of it to the Vienna 

 Exhibition of 1873, inform us that they obtained it by subjecting to 

 distillation with water 400 lb. of aloes, which quantity they estimate to 

 have yielded about an ounce. The oil is stated in a letter we have 

 received from them, to be a mobile pale yellow liquid, of sp. gr. 0863. 

 with a boiling point of 266-271° C. 



Pure aloes dissolves easily in spirit of wine with the exception of a 

 few flocculi ; it is insoluble in chloroform and bisulphide of carbon, as 

 well as in the so-called petroleum ether, the most volatile portion of 

 American petroleum. The sp. gr. of fine transparent fragments of aloes, 

 dried at 100° C, and weighed in the last-named fluid at 16° C, was 

 found by one of us (F.) to be 1364 ; showing that aloes is much more 

 ponderous than most of the resins, which seldom have a higher sp. gr, 

 than I'OO to I'lO. In water aloes dissolves completely only when 

 heated. On cooling, the aqueous solution, whether concentrated or 

 dilute, becomes turbid by the separation of resinous drops, which unite 

 into a brown mass, — the so-called Resin of Aloes.^ The clear solution, 

 after separation of this substance, has a slightly acid reaction ; it is 

 coloured dark brown by alkalis, black by ferric chloride, and is precipi- 

 tated yellowish-grey by neutral lead acetate. Cold water dissolves about 



* Wehave tothank J.W. Akerman, Esq., made by the pharmacopoeia process from 

 of Pietermaritzburg, for the foregoing in- commercial Socotrine aloes containingabout 

 formation as to the manufacture of this 14 per cent, of water, was found from the 

 drug. record of five experiments, in which 179 lb. 



^ Blue Books for the. Colony of Natal for were used, to be 62 '7 per cent. Barbados 

 1868, 1869, 1870, 1871, 1872. ' aloes, which is always much drier, afforded 



* The average yield of aqueous extract on an average 80 per cent. 



