July 26, 1889.] 



SCIENCE 



63 



sugar-sirup are made in the neighborhood of Florence. The 

 oranges imported into Leghorn, whether for consumption or for 

 candying, are nearly all brought from the islands of Sicily, Sardinia, 

 and Corsica, In all the countries contributing the raw fruit for 

 this industry, it is treated in the same manner for the over-sea 

 passage. The fruit is simply halved and placed in hogsheads or 

 large casks filled with a fairly strong solution of brine, the fruit 

 being halved merely to insure thorough preservation of the rind by 

 an equal saturation of the interior as well as the exterior surface. 

 In these casks it arrives at the doors of the manufactory. The 

 first process to which it is then subjected is the separation of the 

 fruit from the rind. This is done by women, who, seated round a 

 large vessel, take out the fruit, skilfully gouge out the inside with 

 a few rapid motions of the forefinger and thumb, and, throwing 

 this aside, place the rind unbroken in a vessel alongside them. The 

 rind is next carried to large casks filled with fresh cold water, in 

 which it is immersed for between two and three days to rid it of 

 the salt it has absorbed. When taken out of these casks, the rinds 

 are boiled, with the double object of making them tender and of 

 completely driving out any trace of salt that may still be left in 

 them. For this purpose they are boiled in a large copper caldron 

 for a time varying from one to two hours, according to the quality 

 of the fruit and the number of days it has been immersed in brine. 

 When removed from this caldron, the peel should be quite free 

 from any flavor of salt, and at the same time be sufficiently soft to 

 absorb the sugar readily from the sirup in which it is now ready to 

 be immersed. The next process to which the rind is subjected is 

 that of a slow absorption of sugar, and this occupies no less than 

 eight days. The absorption of sugar by fresh fruit, in order to be 

 thorough, must be slow, and not only slow but also gradual; that 

 is to say, the fruit should be at first treated with a weak solution 

 of sugar, which may then be gradually strengthened, for the power 

 of absorption is one that grows by feeding. The fruit has now 

 passed into the saturating-room, where on every side are to be 

 seen long rows of immense earthenware vessels, about four feet 

 high and two feet and a half in extreme diameter, in outline roughly 

 resembling the famed Etruscan jar, but with a girth altogether out 

 of proportion to their height, and with very short necks and large 

 open mouths. All the vessels are filled to the brim with citron and 

 orange peel in every stage of absorption ; that is to say, steeped in 

 sugar-sirup of about eight different degrees of strength. Th's pro- 

 cess almost always occupies eight days, the sirup in each jar being 

 changed every day ; and with vessels of such great size and weight, 

 holding at least half a ton of fruit and sirup, it is clearly easier to 

 deal with the sirup than with the fruit. To take the fruit out of 

 one solution and to place it into the next stronger, and so on 

 throughout the series, would be a very tedious process, and one, 

 moreover, injurious to the fruit. In each of these jars, therefore, 

 there is fixed a wooden well, into which, a simple hand suction- 

 pump being introduced, the sirup is pumped from each jar daily 

 into the adjoining one. A slight fermentation next takes place in 

 most of the jars ; but this, so far from being harmful, is regarded 

 as necessary, but is not allowed to go too far. There is yet another 

 stage, and that perhaps the most important, through which the 

 peel has to pass before it can be pronounced sufficiently saturated 

 with sugar. It is now boiled in a still stronger sirup of a density 

 of forty degrees by the testing-tube ; and this is done in large cop- 

 per vessels over a slow coke fire, care being taken to prevent the 

 peel adhering to the side of the vessel by gently stirring with a long 

 paddle-shaped ladle. This second boiling occupies about an hour. 

 Taken off the fire, the vessels are carried to a large wooden trough, 

 over which is a coarse open wire netting. The contents are poured 

 over this, and the peel distributed over the surface of the netting, 

 so that the sirup, now thickened to the consistency of treacle, may 

 drain off the surface of the peel into the trough below. The peel 

 has now taken up as much sugar as is necessary. Next comes the 

 final process, — the true candying, or covering the surface of the 

 peel with the layer of sugar-crystals which is seen on all candied 

 fruits. To effect this, a quantity of crystallized sugar (at Leghorn 

 the same quality of sugar is used as is employed in the preparation 

 of the sirup) is dissolved in a little water ; and in this the now dried 

 peel, taken off the wire netting, is immersed. The same copper 

 vessels are used, and a mixture is again boiled over a slow fire. 



A short boiling will suffice for this the last process ; for the little 

 water will quickly be driven off, and the sugar, upon cooling, will 

 form its natural crystals over the surface of the fruit. Poured off 

 from these vessels, it is again dried upon the surface of the wire 

 netting, as before described. The candying is now complete, and 

 the candied peel is ready for the packing-room, to which it is car- 

 ried in shallow baskets. In the packing-room may be seen hun- 

 dreds of boxes of oval shape and of different sizes, for each country 

 prefers its boxes to be of a particular weight ; Hamburg taking the 

 largest (of 15 and 30 kilograms), the United States preferring 

 smaller (of 10 and 12 kilograms), while England takes the smallest 

 (of 5 kilograms), and one containing about 7 English pounds. 



BOOK-REVIEWS. 



Force and E7iergy. A Theory of Dynamics. By GRANT AL- 

 LEN. New York, Longmans. 8°. $2.25. 



In this work the author presents a new view of some of the con- 

 cepts of physical science. The current views he holds to be erro- 

 neous, and, though he says that he puts forth his work with pro- 

 found diffidence, it is evident that he feels great confidence in its 

 correctness. The essential point in his theory is the distinction he 

 draws between force and energy, both of which he includes under 

 the term " power." Power he defines as " that which initiates or 

 terminates, accelerates or retards, motion." He then goes on to 

 divide power into two varieties, — force, or aggregative power ; and 

 energy, or separative power. Among forces he reckons gravitation, 

 cohesion, and chemical affinity ; and among energies, heat, muscu- 

 lar power in many cases, and, in short, whatever separates bodies 

 or particles from one another. This theory he first states in an 

 abstract form, and afterwards proceeds to an account of the various 

 actual concrete forces and energies in the universe, mechanical^ 

 chemical, and vital, endeavoring to show that his views are not 

 only consistent with the known facts and laws of physical science,, 

 but are essential to a correct understanding of them. 



As to the merits of IVIr. Allen's views, we shall not now enter on 

 any elaborate criticism ; but certainly his use of terms is not accord- 

 ant with the common practice either of scientists or of writers 

 generally. The term " power" has always been used in philosophy 

 to denote causality viewed hypothetically ; as when we say that 

 fire has power to melt wax, meaning that it will melt wax if the 

 two are brought into contact. Force, on the other hand, is com- 

 monly used to mean what Mr. Allen calls power ; namely, any 

 cause that in any way affects motion. The distinction Mr. Allen 

 draws between separative and aggregative powers is of course a 

 real distinction ; and yet he himself finds it impossible to maintain 

 it with perfect consistency. Thus, he calls the motion of a falling 

 body and the contraction of a cooling body, energies, although 

 they are obviously aggregative ; and his attempt to remove the in- 

 consistency does not seem successful. We commend the work,, 

 however, to the attention of our readers, as it is well written and 

 with earnestness of purpose, and will doubtless be provocative of 

 thought. 



Life of Charles Blacker Vignoles. By his son. Rev. OlinthuS 

 J. Vignoles. New York, Longmans. 8". S5. 

 The subject of this memoir was one of the pioneers in railroad 

 engineering, a work which in its early development required far 

 more mventiveness and fertility of resource than is the case now ; 

 and his son has done well in laying an account of his life before 

 the public. The book is well written, and with as much impar- 

 tiality as could be expected in so near a relative of the hero. Vign- 

 oles was born in the last decade of the eighteenth century, and 

 lived to the ripe age of eighty-two. He lost his parents in early 

 life, and went to live with his maternal grandfather, with whom he 

 afterwards had an irreconcilable quarrel. On reaching manhood, 

 he entered the army, and by the aid of influential friends and his 

 own merits rose in a few years to the position of lieutenant ; but 

 the conclusion of peace after Waterloo deprived him of the hope 

 of further advancement, and he came over to America, and went 

 to work as a civil engineer. He was employed in South Carolina 

 and other Southern States, and by his experience there prepared 

 himself for the more difficult work of railroad engineering, in which 



