57 



COLURES. 



COMB MANUFACTURE. 



68 



employed in all the preliminary dispositions of a battle, and it is only 

 when within range that the question arises as to formation. For the 

 offensive, the objects to be kept in view in the formation of troops, are 

 mobility combined with solidity and impulse ; while for the defensive, 

 solidity should be united with the greatest possible amount of fire. 

 Now the column, if not too deep, combines the former qualities in the 

 highest possible degree, and in an attack firing is not required ; indeed, 

 if the men once commence to fire, the attack will in all probability fail, 

 fur the impulse and impetuosity of the charge being lost, if received by 

 a steady fire from the enemy, they soon get into confusion and retire. 

 At the same time it must be remembered, that the deeper the forma- 

 tion the greater will be the carnage, especially if artillery be employed 

 in the defence of the position attacked ; and therefore, if the troops are 

 sufficiently steady and well disciplined to be managed under fire in 

 line they will have a great advantage. The deployment from the column 

 into line for attack, should not however take place at too great a 

 distance from the point attacked, as, especially in moving over rough 

 ground, troops in line soon lose their formation ; whilst on the other 

 hand, if the deployment is too long deferred, and the column while 

 deploying is received with a heavy fire, it is likely to be thrown into 

 disorder, and if then promptly charged, (as at Waterloo), will probably 

 be routed. 



Jomini, while condemning the formation of troops in large masses, 

 as at Waterloo, argues in favour of battalion columns, formed on the 

 utre companies, with two companies as skirmishers, thus making 

 the depth only six ranks, as a good general formation for attack. For 

 he says, that although at Takvera, Busaco, Fuente d'Onor, Albuera, 

 and Waterloo, heavy columns, (in one case twelve battalions deployed 

 behind one another, or a depth of thirty-six ranks,) had been annihilated 

 by the fire and attack of the English infantry in line, on front and 

 flank, yet that this is no proof against small battalion columns, which 

 have not been sufficiently tested. And for defence, he considers the 

 first line should be deployed, and the second in battalion columns. 

 The success, of the line or column will, however, depend upon its 

 proper application by the general, according to the modifying circum- 

 stances of ground, whether broken or even, of discipline and of morale. 

 And no general rule can be laid down, though the Duke of Wellington 

 ]>l" .irs to have almost always deployed his columns before attacking. 



COLURES (<u n6\ovpoi, col6ri). The term originally applied to any 

 great circles of the sphere passing through the poles, but came at last 

 to mean only the circles which also pass through the equinoxes and 

 the solstices, which are distinguished as the equinoctial and solstitial 

 colures. These terms are now of very little use, as the fact of a star 

 being upon either circle is attended with no remarkable phenomenon. 

 Astronomers would describe a star on the equinoctial colure as having 

 either no right ascension, or twelve hours of right ascension, according 

 as it is on the vernal or autumnal half of the circle ; and a star on the 

 solstitial colure as having either six hours or eighteen hours of right 

 ascension, according as it is on the summer or winter side of the 

 us. If we say that the sun is on the equinoctial colure at the 

 quarter-days of March and September, and on the solstitial colure at 

 those of June and December, we rather elucidate the term colure than 

 derive information from it. 



The solstitial colure passes through the poles of the ecliptic also, 

 and might be called an ecliptic colure ; but the other circle, which 

 pones through the equinoxes and the poles of the ecliptic, has no 

 distinct name, and would be best described as the circle from which 

 celestial longitude is reckoned. 



COLZA, OIL OF. The seeds of the Brasnca campestris oleifera 

 yield by expression about 39 per cent, of a yellow oil, which possesses 

 a specific gravity of '9136, and solidifies at 21 Fahr. It is a mixture 

 <if the glycerine compounds of two acids, namely Brattic acid 

 (C 4 ,H, 3 O,). The other acid resembles oleic acid, but does not seem to 

 be identical with it. Colza oil is used both for lamps and in cookery. 



COMA, a Greek word (K&IUL), signifying profound sleep ; a morbid 

 condition of the brain, attended with loss of sensation and voluntary 

 motion, the patient lying as if in deep sleep. 



It can scarcely be considered a primary or idiopathic disease ; it is 

 rather symptomatic of that condition of the brain which, when in 

 sufficient intensity, produces apoplexy. If it be regarded as a posith 

 disease, it must be considered as a milder form of apoplexy. It exisi 

 in different degrees of intensity; several of which degrees, as they are 

 attended with some variety in the symptoms, and are dependent on 

 some modification of the pathological condition of the brain, so they 

 have acquired distinct names. When there is a state of mental and 

 physical torpor, indicated by an almost constant tendency to sleep, and 

 great inaptitude for muscular exertion ; when the patient is sensible 

 only as long as he is strongly excited, and as soon as the external 

 I us is withdrawn, lapses into a state of forgctfulness, the affection 

 is called Lethargy. When no distinct consciousness returns, however 

 the jiatient may be roused or stimulated, though there still remain 

 " Rome indication of feeling on the application of mechanical irritation, 

 as on being pricked or pinched, the affection is called Carus. But 

 when the insensibility is so great that the patient indicates neither 

 MI nor feeling, whatever mechanical stimulus be applied, this 

 state* is often called, by way of eminence, Coma. This comatose state 

 invariably accompanies apoplexy ; and, as Las been stated, coma, when 

 , passes into apoplexy. 



The abolition of sensation and voluntary motion (animal functions), 

 which constitutes coma, is always attended with a greater or less 

 disturbance of the organic functions. The circulating system is dis- 

 ordered ; the pulse at one time is slow and full, and at another quick 

 and small. The respiration is laborious, and is commonly preter- 

 naturally slow. The power of generating animal heat is almost always 

 diminished, the skin being cold and clammy ; though there are cases 

 in which the temperature is elevated somewhat above the natural 

 standard. The countenance is usually pale and sunk; the pupils 

 dilated, but in the worst cases contracted ; the position of the body is 

 supine ; in the worst cases there is a constant tendency to sink down in 

 the bed ; the limbs are motionless ; and the evacuations, if not wholly 

 retained, which is usually the case, are passed without consciousness. 



In coma there is an exhaustion or suppression of the sensorial powers, 

 in other words, an abolition of the cerebral functions. This state of 

 the nervous is always attended with a morbid condition of the vascular 

 system. There is either a congestion of the capillary blood-vessels, 

 occasioning obstructed circulation of the blood through the brain, or 

 there is too rapid and violent a flow of blood through the cerebral 

 vessels; or an inflammatory condition of the blood-vessels; or an 

 extravasation of blood, or an effusion of serum into the cerebral sub- 

 stance. In addition to its disordered motion, there is also sometimes 

 a depraved quality of the blood. There is reason to believe that to 

 some morbid change in the constitution of the blood, the coma incident 

 to bad types and advanced states of fever is mainly owing. 



The morbid condition of the brain, on which coma depends, may be 

 induced by any of the causes which have been enumerated as consti- 

 tuting the predisposing and exciting causes of apoplexy. [APOPLEXY.] 



COMA BERENI'CES (Constellation), the hair of Berenice, placed 

 among the stars by the astronomer, Conon, in memory of Berenice, the 

 wife of Ptolemy Euergetes. (B.C. 246.) The legend is, that she had 

 dedicated this hair to Venus, in case of her husband's safe return from 

 Asia, and that it disappeared from the temple in which it was placed, 

 and was never seen again till found in the starry heavens, where it now 

 is, close to the tail of the Lion, and passing the meridian about an hour 

 before Arcturus. [BERKNICE.] Geniinus attributes the constellation to 

 Calh'machus, who mentions it, as do Catullus and Pliny. Ptolemy 

 does not place the stars now belonging to this constellation by them- 

 selves, but in the tail of the Lion ; and Hyginus makes no separate 

 mention of it. It was constantly mentioned by writers on the sphere, 

 but not figured or catalogued separately, as far as we can find, till the 

 time of Tycho Brand. 



The constellation Coma Berenices will be found shut up in the 

 triangle formuil by thu three bright stars, Arcturus, j8 Leouis, and a 

 Canum Venaticorum. It contains no stars of conspicuous magnitude. 

 COMB MANUFACTURE. Combs are generally made of a thin 

 plate of wood, horn, tortoise-shell, ivory, bone, or metal, which may be 

 either flat or curved, having one or two of its edges indented with 

 narrow slits, which divide the substance of the comb into long, fine, 

 pointed teeth. Combs employed in the woollen manufacture are de- 

 scribed in the article relating to that subject. Curry-combs, used in 

 dressing horses, consist of a number of iron plates notched on one edge 

 to form saw-like teeth,and attached by the other edge to an iron back, 

 in parallel lines, so as to form an instrument the action of which is 

 between that of a scraper, a comb, and a brush. 



In the mode of cutting and shaping the plates of which combs are 

 formed there is little call for remark ; but iu the act of comb-cutting 

 much ingenuity has been called into exercise. The hand-method is by 

 means of a dotible saw, consisting of two separate fine saws, placed 

 parallel with each other, and adjusted to such a distance as to embrace 

 % tooth of the required fineness between them. These two saws are so 

 arranged that while one cuts into the comb to the full depth required, 

 the other cuts only about half that depth ; by this contrivance the 

 uniformity of the comb is secured ; because, while the deeper saw is 

 completing the first cut, the shallower one is forming the commence- 

 ment of the second ; and when, on the completion of the first cut, the 

 deep saw is put into the second cut to complete it, the shallower one 

 immediately commences a third. The cuts thus formed are subse- 

 quently enlarged and rendered smoother by means of a very thin 

 wedge-shaped file, which also points the teeth. With such accuracy " 

 may these operations be performed, that delicate ivory combs, with 

 from fifty to sixty teeth in an inch, are produced in this way. Though 

 this method of comb-cutting is still practised, a superior and much 

 quicker mode by means of circular saws and revolving cutters for 

 pointing the teeth has been long in use. 



By the above-described modes of comb-cutting all the material of 

 the interstices between the teeth, is lost or destroyed; but by the 

 operation known as the partlny of combs such loss or waste of material 

 may be avoided in the manufacture of combs of tortoiseshell, horn, or 

 any other tough material ; two combs being, by this process, made out 

 of one piece, the teeth of one being cut, by the pressure of chisel-like 

 instruments, out of the interstices of the other. Mr. Lyne's machine, 

 for this purpose, is worked by the alternating action of a lever handle. 

 The piece of tortoiseshell or horn is secured upon a traversing carriage, 

 which is capable of motion iu a direction perpendicular to that of the 

 teeth of the comb. This carriage is made hollow, to receive an iron 

 heater, the heat of which softens the horn, and thereby renders it more 

 easy to cut. Between each movement of the carriage the cutter, 



