Vol. XIV. No. 346. 



THE AGRICULTURAL NEWS. 



249 



Extraction of Tannin from Wattle Bark. 



Reference isinade in The B ird>of Trade Journal 

 for June l<>. L915, to the ei 



., al Mer< bank.Natal, for di L^ig m ith the wattle 

 bark on a new system, in wh i i ■ nts have been 



carried out for some time past. Thus new process for 



cting tannin from green wattle bark consists in 

 subjecting the bark to i chanical pressings 



by means of heavy bronze rollers, and applying hoi 

 water and tanned liquor washes tp the pressed bark 

 between each sel of rollers. Th< extraction is effi 

 within a period of two minutes, and no darkening 

 colour is possible as occurs in the process of leaching 

 in pits. 



h might be added i hal . ac :i rding to the report for 

 1!> 1 4- 'il the Durban Chamber of < !<&mmerce, the Natal 

 wattle bark trade lias suffered a check b\ reason oi 

 the war. The exports for i he even months of 



1!)14 amounted to 17,663 tons as compared with 

 39,899 tons in the corresponding period of the previous 

 i Inn the total amount exported in L914 was onlj 

 58,132 tons, valued .-it £286,399) as compared with 

 65,042 tons, valued al £309,268, in 1913. Had condi 

 tions been iM.nnal.it is stated, the exports for 1914 

 would ha\ ■ exceeded I hose of 19] :;. 



Classification of Sweet Potatoes. 



In the Sweet Potato Number of The Philippic 

 Agricu and Forester, Vol.,'III, No. 6, there is 



given in a paper by Apolonis Ramos Manoz on the 

 identification and tests of varieties of sweet potatoes, 

 a lv\ devised by Dr. Groth for the classification of 

 varieties of sweel potato, which should prove "t 

 considerable value in tin- work ofselecting desirable 

 varieties for propagation. The system "I' classification 

 is based on the character ami habit of the 

 varieties, thai is to say— (a) shape of the leaf, (b) size 

 of the leaf, (c) length of stem nh colour of stem. 



I . i -!/.■ .if st> 111. (t I presence i if Mar. (g) colour "I lower 



surface ot veins, (h) arrangement of hair on upper 

 mii tare of leaf, ( i ) outside colour of tubers, (j ) colour of 



the Mesh of the tubers, (k) distinctness of w 1 elements 



in tubers, and (1) flowering habit. As will he seen on 

 nr>- to the ll"'s/ 1 iidui it Bulletin, Vol. XII, p. 521, 



this classificati liffers somewhat from that adopted by 



Mr. \V. Robson, Curator «.t the Botanic Stal , 



Montserrat, in his attempt to classifj the varieties of 

 sweet potatoes then in cultivation at the Montserrat 

 Experiment Station. Mr. Robson's system, which was 

 that originally adopted by R. A. Price, horticulturist of 



the Texas Experiment Stati n 1893, divided sweel 



potatoes mi" tlnve groups having (a) split or lobed 

 foliage, (lii shouldered or slightrj lobed foliagi and 

 ,,-) round or i ntire foliage 



The author of the paper under consideration, 



whilst adopting Dr. Groth's kej and classification in 



pieference to Mr. Robson's, emphasizes the fact that 



different varieties of sweet p itato hav dim n at 



;abilitv to vield, and have different taste as well 



as colour; thai bher< bra early, eai lj somew hat 



early, late and vorv |al 5: I hat some ire 1 



d by drought and some are quite resistant; that 

 some are suscept iblc to disease md ot hers aln 

 from disease; and that unless irrigation is feasibL 

 level ctdture should bi tring dry ^e..s..n-. 



and the ridge cultun otherwise. 



In reference to 1 Ins last m as to tl 



ditions under which level culture or ridgi 



should he emploj ed, thi pap dns a su 



conclusions arrived al from experiments in ridge and 

 level cultures, which should receive attention In the 

 West Indies. 



Bullock Creeping Grip Tractor. 



This is the name ot' a new small tractor machine, 

 which it is said more nearly reaches the needsofthe 

 modern sugar planter than any previously seen. The 

 Louisiana Planter for June 19, 1915, gives particulars 

 ot 1 Ins machine and 1 In' results of a demonstration t hat 

 was made recently at Audubon Parkin combination 

 with two mould hoard ploughs cutting L2-inch furrows. 

 These ploughs were of tic sulkj style and were gauged 

 and guided by one man, while tie tractor was managed 

 by another man. The demonstration is said to have 

 been wonderfully successful, and would seem to show 

 that the inventors have' finally got their tractors down 

 to a usable size that will quickly lead to their general 

 use in sugar-cane countries. 



A very notable feature of this tractor is said to 

 1 he short circle in which it cat) turn: it can turn in less 

 land than is ordinarily required for the four-mule team 



and turns more easily than s 1 heavy two-mule teams. 



It was demonstrated that the turn could be on a 

 narrow headland. The creepers are 6 feet in length, 

 and the turn around completely was made with the 

 ploughs hitched to the creeper m a circle 8 feet in dia- 

 meter. Thisseems almost impossible, but these tractors 

 are so built that their 6-foot wheel base is all in 

 contact with the ground undei pressure, that portion 

 between the two axles being forced down to the ground 

 by a patented spring device so that the who],' wheel 

 base utilizes everj corrugation ofits wide belt chain. 

 The motor is so adjusted also, that the wheels on one 

 side can be turned in one direction, and those on the 

 otlar side in the reverse direction and the whole 

 machine move around as though swung on a pivot, 

 thus succeeding in a way,says the journal, that we have 

 in ver seen done so successfully before. 



The machine, it may he added, weighs 2J short 

 tons; several of them are alreadj in use on Louisiana 

 plantations: the builders are making live sizes and 

 are offering to supply the machines al less prices than 



would be the cost of the mules doing the same work. 



Those interested are advised to consull the builders 

 (X. .1. Doud, Southern Distributor, 314 Hennen 

 Building, New Orleans), as these machines have alreadj 

 demonstrated their effectiveness and no longer remaiu 

 an experiment. 



