SPINET SPINOLA. 



357 



primary form of this _ species is the regular octahe- 

 dron ; and this is the figure under which it gener- 

 ally occurs. It is rarely modified by the truncation 

 or the bevelment of its edges, and sometimes pre- 

 sents itself in hemitrope crystals. Its crystals vary 

 in dimensions, though they are usually not above 

 the size of a pea. Their cleavage is very difficult ; 

 fracture conchoidal; lustre vitreous; colour red, 

 passing into blue and green, also into yellow, brown 

 and black; transparent to opaque; hardness above 

 that of quartz; specific gravity 3-5. The red 

 varieties of spinelle are called, by jewellers, spinelle 

 ruby, while those possessed of a darker colour are 

 called Ceylonite or Cleonaste. The following ana- 

 lyses the first of which is by Berzelius, the second 

 by Klaproth, and the third by Descotils exhibit 

 the chemical composition of the species : 



Alumine, 

 Silex, 

 Magnesia, 

 Oxide of iron, 



Lime, 



I. nine 

 Spine!l. 



72-25 

 5-45 

 14-63 

 4-26 

 . 0-00 



96-59 



74-50 

 15-50 

 8-25 

 1-50 

 0-75 



100-50 



3. Pl*>. 



68-00 

 2-00 

 12-00 

 16-00 

 0-00 



98-00 



The red varieties, exposed to the heat of the blow- 

 pipe, become black and opaque; on cooling, they 

 appear first green, then almost colourless, and at 

 last re-assume their red colour. They are with 

 difficulty fused with the aid of borax melting, 

 however, a little more easily with salt of phospho- 

 rus. Pleonaste yields a deep green colour to the 

 globule. The original depositaries of this species 

 are white limestone and a drusy volcanic rock. It 

 is often found, however, in more recent deposits, 

 formed by diluvial or alluvial action, along with 

 crystals of corundum and zircon. The isolated 

 crystals chiefly come from Ceylon. In Siidermann- 

 land, in Sweden, bluish and pearl-gray varieties 

 occur, imbedded in granular limestone. Crystals 

 of a green colour are found imbedded in the drusy 

 cavities of rocks ejected by Vesuvius. But the 

 United States surpass the rest of the world, both 

 as to the number of the localities of spinelle, and 

 the dimensions of its crystals. It abounds particu- 

 larly in the towns of Amity and Edenville, in Or- 

 ange county, New York ; at which places it occurs 

 in a highly crystalline, white limestone, and like- 

 wise loose in the soil, in crystals varying from the 

 size of a pea and under, to those whose smallest 

 diameter is four inches. Their colours are either 

 black, or dark greenish, or bluish black, though it 

 is rarely of a pale pink, or reddish-brown. These 

 crystals are associated with hornblende, mica, au- 

 gite, idocrase and scapolite. Spinelle of a rich 

 green colour is also found in the county of Sussex, 

 New Jersey. The crystals from this spot are 

 highly modified in their figure, and are sometimes 

 nearly transparent. Green and blue spinelle is also 

 found in Massachusetts. Clear and finely-coloured 

 red varieties of the present species are highly prized 

 as ornamental stones in jewelry. They go gener- 

 ally by the name of spinelle ruby, or balas ruby. 



SPINET : a stringed instrument, formerly much 

 in use, but now superseded by the pianoforte, 

 somewhat similar to the harpsichord, and, like that 

 consisting of a case, sounding-board, keys,' jacks, 

 and abridge. The difference between the spinet 

 and the harpsichord is, that the latter is larger, and 

 contains two or three sets of jacks and strings so 

 disposed and tuned as to admit of a variety of 

 stops, while the former has one set of jacks and 

 strings, and consequently only one stop. When the 



spinet was first brought into use, though its inven- 

 tion was certainly anterior to that of the harpsi- 

 chord, is not exactly known. But that it is de- 

 rived from the harp is evident, from its character 

 as well as construction, internal and external ; and, 

 indeed, it was originally called the couched harp, 

 since denominated spinet, from its quills, which 

 resemble thorns, called in Latin spince. 



SPINNING. When the fibres of cotton, wool, 

 or flax, are intended to be woven, they are reduced 

 to fine threads, of uniform size, by the well known 

 process of spinning. Previously to the middle of 

 the last century, this process was performed by hand, 

 with the aid of the common spinning wheel. Locks 

 of cotton or wool, previously carded, were attached 

 to a rapidly revolving spindle, driven by a large 

 wheel, and were stretched or drawn out by the hand, 

 at the same time that they were twisted by the 

 spindle, upon which they were afterwards wound. 

 Flax, the fibres of which are longer and more paral- 

 lel, was loosely wound upon a distaff, from which the 

 fibres were selected and drawn out by the thumb and 

 finger, and at the same time were twisted by flyers, 

 and wound upon abobbin, which revolved with a velo- 

 city somewhat less than that of the flyers. The 

 manufacture of flexible stuffs by means of machinery, 

 operating on a large scale, is an invention of the last 

 century. Although of recent date, it has given 

 birth to some of the most elaborate and wonderful 

 combinations of mechanism, and already constitutes, 

 especially in Britain, an important source of na- 

 tional wealth and prosperity. See Cotton Manu- 

 facture and Woollen Manufacture. 



SPINOLA, AMBROSE, marquis of, one of the 

 most distinguished generals of his age, was born at 

 Genoa, in 1569. His brother Frederic, who had 

 been appointed to the command of the Spanish 

 fleet on the coast of the Netherlands, induced him 

 to join the Spanish forces in the Low Countries, 

 with 9000 Italian and Spanish veterans. After the 

 manner of the old Italian condottieri, or leaders, 

 who collected forces on their own account, and then 

 served at their head in the pay of the Italian states, 

 he was permitted to pay his troops himself, and to 

 receive his compensation from the Spanish treasury. 

 This circumstance, at a time when the conduct of 

 wars depended so much upon the trdops being paid 

 regularly, and the best concerted expeditions failed 

 for want of money, assured him of the success which 

 soon rendered him so celebrated. While mutiny 

 and insubordination prevailed in the rest of the 

 army, his 9000 Walloons were models of discipline 

 and order. The archduke, Albert of Austria, whom 

 Philip II. had appointed governor of the Nether- 

 lands, employed Spinola in the capture of Ostend, 

 which had been so long besieged by the Spanish 

 troops, that Albert despaired of reducing it. Spi- 

 nola was more successful : it fell into his hands in 

 1604, after having sustained a siege of three years 

 and two months. He obtained possession of a mere 

 heap of ruins, but his reputation was at once spread 

 over all Europe, in which every eye was fixed upon 

 this siege. Spinola hastened to Madrid, to give 

 the feeble Philip information of the state of his 

 troops, and received full powers to suppress their 

 disorders. He was named commander-in-chief of 

 all the Spanish and Italian forces in the Nether- 

 lands. On his way back to the theatre of war, he 

 had a conversation with Henry IV., at Paris, who 

 inquired of him his plan for the next campaign. Spi- 

 nola explained to him all his designs without re- 

 serve ; but Henry supposing that this was a mere feint, 



