fgo 



THE TROPICAL AGRICULTURIST, [June i, 1887. 



enclosed valves. This species has a wide ran^ p from 

 the south of Queensland to Spencer's Gulf. Like the 

 amygdaUna it presents two very difftreut extt rnal 

 appearances, one of which is known as a white gum on 

 account of the fmooth pale siom left by the dtcidous 

 bark, the other as Yiclorian ironbark on account of 

 the fissured hardness of the retained bark. This bark 

 is pretty rich in kino. 



E. Qnacrorrhyza-.—Ihe leaves are long and equally 

 green on both sides, with the oil dots hidden, the 

 operculum is as long as the tube, and is concavely 

 attenuated to a sharp point, the anthers are kidney 

 shaped, opening by slits, the stigma is not broader 

 than the apex of the style, the fruit is hemispheriral 

 below with a convex border, and the valves much 

 inserted. The species is very widely spread in Victoria 

 and New South Wales, being the commonest of the 

 stringy barks in Victoria. The trees are gregarious, 

 and there is a great demand for their timber on 

 account of the readiness with which it splits for the 

 manufacture of rails and shingles. They often occur 

 mixed with E. Obliqua. 



E. ohliqua has its leaves equally green on the two 

 sides, and shining with the oil dots concealed. The 

 specific name was given to indicate the marked in- 

 equality of the leaves at the base, but this is a feature 

 in the leaves of many eucalypts. The calyx is rough, 

 and its tube is longer than the hemispherical oper- 

 culum, the fruits are truncate ovate with the border 

 compressed and the valves enclosed. The trees occur 

 gregariously in large forests to be met with between 

 St. Vincent's Gulf and Gippslaud, but not spreading 

 far into New South Wales, they furnish most of 

 the ordinary sawn hardwood. The two last species 

 although their yield of oil is not high, offer con- 

 siderable advantages to the distiller by reason of 

 their gregarious habit and their vogue as hardwood 

 timber trees, which makes the gathering of their 

 leaves cheap. 



E. rostrata : — The leaves are of the same colour on 

 both sides and of a lanceolate shape, the veins 

 are crowded, and the oil, dots though visible are 

 scanty ; the flowers occur in solitary umbels of from 

 4 to 14 flowers, the operculum is longer than the semi- 

 globular tube, from its hemispherical base it rises 

 into a beak-like prolongation, from which the specific 

 name was taken ; the anthers are ovate with longi- 

 tudinal slits, the fruit is roundish with a protruding 

 convex rim, and three, four or five highly exerted 

 triangular valves. This species is found chiefly along 

 the river margins of south-east Australia. 



E. odorata has equally dull leaves with the veins 



spread out at an acute angle. The operculum varies 



in shape from broad couical to bossed hemispherical, 



and is shorter than the calyx tiibe ; the antlers are 



small and roundish, with pore-like slits, the fruit is 



bell shaped, with valves enclosed. The species is 



almost entirely confined to South Australia in the 



neighbourhood of Spencer's and St. Vincent's Gulfs. 



It is probable that in Victoria the E. Melhodora has 



sometimes been confounded with E. odorata, to which 



it is closely allied, and to which it is very .similar, 



the most salient point of distinction between the 



two is that the fruit of E. melliodora is decidedly 



contracted at the summit, while that of E. odorata 



preserves the pure bell-shape.— C7i«»iis/ and Dn(ff(/ist 



of Australasia. 



^^ 



THE SUGAR CANE AND THE SUGAE 

 INDUSTRY AT MAURITllUS. 

 (Translated for the " Tropical Agriculturist " fromthe 1st 

 number of the ''Revue Agrico/e.") 



Mauritius, Jan. 1887. 

 The sugar cane (Saccharum officinarum) is a 

 gramineous plant, which appears ind genous to India 

 and Irdo-Chma, whence it has extended from time 

 immemoral to the Oceanic Islands. 



Towards the middle of the 13th century the traders 

 who carried on commerce with India brought home 

 with them this plant, and introduced it into Arabia, 

 whence it was extended to many points in the basin 

 of the Mediterranean, notably to Egypt, Spain, Sicily 

 aud up to the South of France, 



The sugar yielding reed was soon transported into 

 Madeira, thence in 1420 to the Canaries, and in 1506 

 the Spaniard P. d'Airan<;a introduced it into St. 

 D mingo, where it multiplied rapidly. Gonzalis de 

 Meloza established the first sugar factories there. In 

 1643 the English began to cultivate cane at Barbadoes, 

 ai d the Fieiich at St. Christopher's in 1644, and at 

 Guadelc upe in 1648. 



For a long time the process of extracting the juice 

 of the cane remained in a rudimentary state. The 

 mills moved by bullocks or mules, were composed of 

 three vertical cylinders. Two men, placed one on each 

 side passed the canes, first between the cylinders the 

 widest apart, and then through those which were 

 closer together. As it was necessary to hold the 

 canes in the hand to keep them hor.zontal in going 

 through the vertical cylinders, it frequently happened 

 that the men thus employed were from carelessness, 

 or when overpowered by sleep, subject to having their 

 fingers caught between the cylinders, the rotary move- 

 ment of which was very rapid, and the whole arm 

 and sometimes a portion of the body were crushed 

 before theni was time to stop the mill. 



Stedman, in his voyage to Guyane, relates that in 

 the sugar factories of that colony there was a well 

 sharpened axe kept near the cylinders, for the pur- 

 pose of cutting off an arm, in case of such an accident. 



The use of horizontal cylinders and of water wheels 

 and wind-mills, were so many steps in advance, which 

 were successively realized, to be superseded at the 

 present time by steam power. 



The process for extracting sugar from the juice of 

 the cane followed the same steps. At first the manu- 

 facturers were content to carry on the evaporation by 

 means of single boilers. Afterwards these were arranged 

 in rows (batteries). Towards 1840, Howard constructed 

 for refining purposes the first apparatus for boiling 

 in vacao, and in 1840 Mons. Rillieux conceived 

 the idea of employing the steam developed by 

 the boiling juice to evaporate another portion of 

 the juice, and constructed the first apparatus for pro- 

 ducing the two effects (appareil a double effet), 

 which Mons. Tischbein introduced into Europe in 

 1880, and which Mons. Robert, a Seelowitz, modi- 

 fied so as to produce a triple effect. 



During three centuries, the system of "purging" 

 (egouttage) for the purpose of separating the molasses 

 from the crystals of sugar contained in the concen- 

 trated juice, set in a mass by cooling, remained the 

 same. The boiling mass was placed in forms, barrels 

 or cases, the bottoms of which were pierced with 

 holes, through which the molasses escaped. To expel, 

 more or less completely, the molasses adhering to 

 the granulations, cane juice concentrated to 32 degrees 

 Baume (this was what used to be called clearing 

 le clair(;age) or a thick layer of wet clay was poured 

 over the surface of the sugar, the water from which 

 percolated through the sugar, clearing the crystals of 

 molasses. The latter was called claying (le tenage). 



In 1849 Mons. Serigue invented the plan of apply- 

 ing centrifugal force to drive out the molasses held 

 in suspension by the boiled mass of sugar, and 

 constructed the first turbine. 



The processes adopted for purifying the cane juice 

 remained equally stationary for three centuries, and 

 until towards 1848 the sugar maker confined himself 

 to adding a little lime to the juice, though the pro- 

 portion of this agent, was in no degree based on scientific 

 principles. In 1849 Mons. Melsens suggested the use 

 of bisulphate of lime which was soon abandoned— as the 

 proper way of using sulphurous acid for depriving cane 

 juice of colour was then insufficiently known. Then 

 came carbtnatation di.scovered by Mons. Rousseau, 

 the application of which to the manipulation of cane 

 juice gave but quf'Stionable results. 



In 1867 the lamented Dr. E. leery made the first 

 important and practical use of sulphurous acid, which 

 he employed in the form of monosulfite of lime, at 

 the same time he taught the rational employment 

 of sunflower paper (papier au tournesol) to test the 

 cane juice in regulating the quantity of lime to be 

 used for the purpose of separating the mucilage 

 from the cane juice. At last iu 1880, Messrs. C 



