Vol. I. No. 



THE AGItlCULTURAL NEWS. 



99 



CITRATE OF LIME. 



SWEET POTATOS FOR EUROPE. 



INTERESTING EXPERIMENT. 



As already announced in thr West InJiaii Bul- 

 letin, Vol. II, \)]). 301-2, on the suggestion of Sir 

 Frederic Hodg.son, the Governor of Barbados, efforts 

 have been made by the Imperial Dej)artinent of Agri- 

 culture to find an opening for the suiplus supply of 

 sweet potatos in the island by shipping them to Europe. 

 The matter was activeh' taken up in the autumn of 

 1901, and since October last, regular shipments have 

 been made by every mail steamer. In order to over- 

 come the difficult}' encountered in attempting to 

 introduce a new T'egetablo, due to a want of kni:)wledge 

 of how to cook it, an attractive jianiphlet was pre})ared 

 suggesting fifteen diti'erent ways of |)roparing sweet 

 potatos for table use. Several thousand copies of this 

 have been distributed. 



The results of one set of trial shipments from 

 October 1901 to May 1902 are contained in a letter 

 just received from Mr. J. R. Bovell, the Superintendent 

 of the Botanic Station, who has taken a deej) interest 

 in the matter. Mr. Bovell wrote to the Commissioner of 

 Agriculture on the 10th instant, as follows: — 



I forward a ineinorandmn on the results of the 

 forty barrels of sweet potatos sliiiijied to Messrs. James 

 Philip tt Co., of London, towards the close of the last and 

 the beginning uf this year. 



As you will observe, the results are so far sati.sfac- 

 tory. The average profit derived from shipiiing the jiotatos 

 ivas $18'58 per acre more than would have l>een obtained for 

 them if sold locally ; or an increase of !?5{5'64 per cent. 

 The average expenses per barrel of potatos, including iligging, 

 packing, cooperage, carriage, lighterage, and freight, was 

 $1"06 ; and the average profit jier barrel, after deducting the 

 cost of potatos and the expenses, was 50 cents {'2s '2d). 



As showing what an additional gain of $18'-58c per 

 acre would be considered in .some countries, I append the 

 average gross value, i>er acre, of some of the principal croiis 

 in the U.S. of America, for the ten years 1891 to 1900 

 inclusive, ■ viz : Indian Corn, $!7'98. ; Wheat, $843.; Oats, 

 $7-01. and Barley !?9-55. 



The results of a second set of shipments will 

 be published later. It is evident, however, that, if 

 taken up on right lines and carefully and judiciously 

 pursued, the jjmspects of finding a favourable market 

 for sweet potatos in Europe are jjracticall}' assured. 

 During this year, owing to the low price of sugar, 

 large areas have been planted in sweet potatos at 

 Barbados. It is hoped that the planters will do all 

 they can to follow up the experiments initiated by 

 the Department of Agriculture, and that they will be 

 successful in establishing a market for sweet potatos 

 in Europe and so help to tide over a serious crisis in 

 the history of the island. 



Pl!.A.(TirAL DEMONSTRATION AT DOMINICA. 



On Saturday, Maj- 24, Mr. Watts gave a demon- 

 stration at the Bath estate, Donuniea, of the process 

 of making citrate of lime on a connuercial scale, for the 

 information of those interested in the lime juice 

 industry in Dominica. Mr. Frampton, the manager 

 kindly placed the works and ai.)pli;xnces at Mr. Watts' 

 disjDosal and gave very valuable assistance in carrying 

 out the experiment. 



Three hundred gallons of linu' juice were heated 

 nearly to boiling jioint in an exteniporized steam pan, 

 the juice was then neutralized with chalk and the 

 heating continued until the precipitated citrate of lime 

 was crystalline. . Filtration was effected by means of 

 strong twill cotton bags sujjportod within strong canvas 

 c<ivers. These, though acting efficiently as filters, did 

 not permit of such efficient washing of the citrate as 

 was desirable. 



When well drained the wet citrate was removed to 

 the cacao drier in the Botanic Station and thoroughly 

 dried. (For description of this drier see p. 19.) 



There were two points which could not be readily 

 demonstrated. The first was the proper washing of the 

 citrate with hot water. The second was the removal 

 of a large proportion of the water from the citrate by 

 pressing it befu-e putting it in thi'' drier. Efficient 

 jjressing will mati^riaJly shorten the drying process. 



The citrate, when dry, was of good colour, being 

 nearly white : it was quite crystalline and thus was 

 readily wetted and diflused through water. On analysis 

 at the Government Laboratory for the Leeward Islands 

 it was shown to contain 70'fS per cent, of citric acid, 

 and to contain no carbonate of lime (free chalk). When 

 boiled with water it did not impart any dark colour. In 

 all resjjects it ajjpeared to be a satisfactory commercial 

 sample of citrate. 



Its value depends on the price of concentrated 

 juice. If the price of concentrated juice is 



£17perpipe, the sample is w^orth £3 2 6 per cwt. 

 £15 " " " " £2 15 2 



£13 " " " " £2 7 9 



There was a good attendance id' planters and 

 othei-s during the lienionstration : they all appeared to 

 be highly interested in the process and in Mr. Watts' 

 exjilanation of the various ojjerations. 



Unusually heavy rains fell during the progress of 

 the work, but this, except for the inconvenience caused, 

 in no way rendered the process of drying the 

 citrate difficult. It is interesting to observe this, for it 

 has .sometimes -been asserted that it will be difficult to 

 make citrate in Donuniea and other West Indian 

 islands because of the damp climate. The present 

 experiment clearly showed that there is no ground for 

 this stiggestion. 



