Vol. VIII. No. 176. 



THE AGl'JCULTURAL NEWS. 



21 



In the over-ripe banana.s, the proiiortion of sucrose shows 

 a falling off (10-36 per cent.), which is explaiued-by the fact 

 that inversion of the sucrose into glucose and fructose takes 

 place. The latter two products also undergo further breaking 

 up, which probably accounts in part for the large amount of 

 carbon dioxide formed in after-ripenifig. 



Mangos also are usually picked when unripe. At that 

 time they are hard, acid, and flavourless, but the after-ripen- 

 ing process renders them tender and full-flavoured in a few- 

 days. 



The chief features of the ripening process with the 

 mango are changes in the proportions of starch, sucro.se, and 

 citric acid, together with a loss in weight. Five mangos, 

 ■which originally weighed 1,139'3 grammes, lost IS grammes 

 in weight, when kept for three days in a cool place. Of this 

 loss, 4'.5.5S grammes consisted of carbon dioxide. As in the 

 case of the bananas, a mango fruit from a parcel having 

 practically the same initial maturity was daily analysed. 

 As a result, it was observed that the proportion of starch 

 pre.sent declined from 8 53 in the unripe mangos to nil in the 

 ripe fruit, while on the other hand, during the same period, 

 the sucrose increased from 2'.57 to 1227 per cent. Later on 

 the sucrose becomes hydrolysed and split up into glucose 

 and fructose. Citric acid, which is the only acid found 

 present in the mango, diminished from r31 per cent, in the 

 unripe stage, to O'lO in the ripe fruit. The acid is not 

 neutralized in any way during the ripening process, but is 

 destroyed as the result of the respiratory process, and given 

 oil' chiefly as carbon dioxide. 



Tamarinds were also dealt with, and the composition of 

 the pulp of these fruits, in several stages of ripenes.s, extend- 

 ing over a period of more than two months, is given by 

 Mr. Geerligs. Starch was present in green tamarinds to the 

 extent of 333 per cent., but five weeks later all the starch 

 hail lieen transformed — not into sucrose — but into a mixture 

 of glucose and fructose. During the ripening jirocess, the 

 proportion of these two sugars present increased from 040 

 and 33 per cent, to 20'4 and 11 '6 per cent, respectively. 

 The acid of the tamarind is tartaric acid ; of this, the total 

 proportion present in the green fruit is 48.5 per cent., and in 

 the ripe fruit, 16-4 per cent. In ripening, too, a large amount 

 of water is evaporated, causing the fruit to shrink consider- 

 ably within the pod. A good deal of acid is consumed by 

 respiration after the tamarind has reached the stage of 

 ripeness. 



Another tropical fruit, the ripening of which was inves- 

 tigated, is the sapodilla. Sapodillas are plucked tree ripe, in 

 which stale they are green and hard, and contain gutta-percha 

 and tannin di-ssolved in the .sap, which render the fruit unfit 

 for eating. After keeping for a short while, however, the 

 gutta-percha and tannin become in.soluble, and the fruit 

 becomes full-flavoured and palatable. In the ripe sapodilla, 

 the coagulated guttapercha may be seen as a series of white 

 thread.s, while the tannin is deposited as insoluble matter in 

 certain cells. 



These changes constitute the whole phenomena of ripen- 

 ing in the case of the .sapodilla. There is no transformation 

 of starch into sugar, since no starch whatever exists in the 

 fruit at any stage of the ripening process. Further the 

 amount of sugar present before and after full ripening is the 

 same. 



It may be added that from the result of experiments 

 described in detail, Mr. Geerligs comes to the conclusion that, 

 in the case of the banana and the mango, the rapid trans- 

 formation of starch into sugar is one of the vital processes 

 of these fruits, and not a consequence of the action of some 

 enzyme or soluble ferment. 



PIPE CALABASH AT GRENADA. 



In reference to tlie note on thu Pipe Calabash at 

 St. Lucia, which was given in the Agricaltural Neivs 

 of December 12 last (page 389), Mr. R. D. Anstead, 

 Agricultural Supt-rintendent of Grenada, writes as 

 follows, under ilate of December 28 last: — ■ 



It will be of interest to you to know that the seed of 

 Lii'/enaria vulgaris received here at the end of June last 

 from St. Lucia grew readily, and that a number of plants 

 were raised from it. These fruited freely, and the fruits are 

 now ripening ofl'. 



The jdants were allowed to climb, so that none of the 

 fruits develiiped curved necks naturally. Exiieriments were, 

 however, conducted with a view of producing the curve by 

 making the fruits press against flxed supports, stakes, etc. 

 Some success was obtained, and the experience gained will, 

 I think, enable us to obtain gourds of the required shape 

 from the next crop. 



SOIL SURVEY WORK. 



A work of great value to agriculturists in the 

 United States, more especially to those who propose to 

 enter upon the cidtivarion of land in new districts, has 

 been carj-ied on by the Soil Survey of the Bureau of 

 Soils dtiring the last ten years. The character of 

 a good deal of the land surveyed is unknown, and the 

 work aims at showing the suitability and capacity of 

 this land for new crops and industries, the information 

 thus provided supplying in great part the local experi- 

 ence of agricidtiirists which is available in older 

 countries. 



Soils are examined to detennine (1) their texture, or the 

 relative amounts of coarse and fine particles of which they 

 consist ; (2) their structure, or the relationship of these 

 particles ; (3) the proportion of organic matter present, and 

 (4) their natural drainage and topography. Soils which are 

 closely similar in all these respects are said to belong to the 

 same soil type, and under similar climatic conditions the 

 type is capable of producing similar crojjs. At present nearly 

 five hundred types of soil are recognized. Several soil types 

 in a given region difl'er only in texture, and are similar in 

 other respects. Such a group of soils is called a series. 



In the reports of the Soil Survey officials, the charac- 

 teristic appearances of the various soil types, together with 

 the uses to which they are put, and the agricultural methods- 

 adopted, are described in detail. The value of these 

 reports is increased, since they contain, in every case, an 

 account of the crops raised in other areas where the same 

 type of soil has been met with, and suggestions are made as 

 to new croi)s or new methods. 



From these reports the individual farmer may learn the 

 relationship of the soil upon his own holding, not only to the 

 other soils in the immediate neighboiu-hood, but also to soils 

 of the same character in widely sejiarated regions. He may 

 thus observe the results obtained by other farmers upon suchi 

 .soils, and apply their experience to his conditions. 



According to the Yearbook of the U.S. Department of 

 Agriculture, the area surveyed and mapped in 1906-7 was 

 13,158,400 acres, and there have been completed to June 30, 

 1907, surveys covering a total of 89,118,080 acres. Tha 

 work has been so distributed as to include every large repre- 

 sentative district in the United States, and has given 

 a knowledge of the soil resources of the colony far beyond 

 what was ever conceived of before. 



