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point which he was anxious to examine, says : ' The 

 country wore the same aspect, till at last the fine green 

 turf became more wearisome than a dusty turnpike -road. 

 We everywhere saw great numbers of partndgea (TVnoMW 

 ntfi'(cens). These birds do not go in coveys, nor do they 

 conceal themselves like the English kind. It appears a 

 very silly bird. A man on horseback, by riding round anil 

 round in a circle, or rather in a spire, so as to approach 

 closer each time, may knock on the head as many as he 

 pleases. The more common method is to catch them with 

 a running noose or little lazo, made of the stem of an 

 ostrich's feather, fastened to the end of a long stick. A 

 boy on a quiet old horse will frequently thus catch thirty 

 or forty in a day. The flesh of this bird, when cooked, is 

 delicately white.' (Journal of Researches in the Countries 

 rixited by H. M. S. Beagle.) 



TIXCA, a genus of fishes founded by Cuvier, and which 

 has for type the common tench, Cyprinus tinea, Linn. : 

 TnK-a. rulgaris, Cuv. This fish belongs to the carp family 

 (Cyprinidee'), and is separated genetically on account of the 

 small size of the scales with which the body is covered, 

 combined with the small antero-posterior e'xtent of the 

 dorsal and anal fins, both of which are destitute of the ante- 

 rior bony spine or any such as are observable in some allied 

 fishes as in the dorsal fin of the barbel for instance ; the 

 barbules to the mouth are very small. 



The tench, observes Mr. Yarrell, inhabits most of the 

 lakes of the European continent. In this country, though 

 frequent in ornamental water and ponds, it is but sparingly 

 found in the generality of our rivers. There is some doubt 

 whether, like the carp, its origin be not foreign, and 

 whether those rivers that can now boast of it are not in- 

 debted for it to the accidental escape of fish from the pre- 

 served waters of neighbouring gentlemen. The rivers it is 

 mostly in are those which are slow and deep, and in such 

 situations it does not appear to be so prolific as in ponds. 

 Cuvier observes that the tench inhabits by preference 

 stagnant waters. This is in accordance with the observa- 

 tions of .Mr. Yarrell, and, rivers being an unnatural habitat 

 for the fish, will account for their being less prolific in 

 such situations. 



The author of the interesting work on British Fishes, 

 just mentioned, quotes the following account illustra- 

 tive of the habits of the tench and of its tenacity ofr life : 

 it U from Daniel's ' Rural Sports :' ' A piece of water 

 which had been ordered to be filled up, and into which 

 wood and rubbish had been thrown for years, was directed 

 to be cleared out. Persons were accordingly employed ; 

 and, almost choked up by weeds and mud, so little water 

 remained, that no person expected to see any fish, except- 

 ing a few eels, yet nearly two hundred brace of tench 

 of all sizes, and as many perch, were found. After the 

 pond was thought to be quite free, under some roots there 

 seemed to be an animal which was conjectured to be an 

 otter ; the place was surrounded, and on opening an en- 

 trance among the roots, a tench was found of most singular 

 form, having literally assumed the shape of the hole, in 

 which he had of course for many years been confined. 

 Hi* length from eye to fork was thirty-three inches ; his 

 circumference, almost to the tail, was twenty-seven inches : 

 his weight eleven pounds nine ounces and a quarter; the 

 colour was also singular, his belly being that of a char, or 

 veimilion. This extraordinary fish, after having been in- 

 spected by many gentlemen, was carefully put into a pond, 

 and ;it the time the account was written, twelve months 

 afterwards, was alive and well.' 



Experiments have shown that a tench is able to breathe 

 when the quantity of oxygen is reduced to a five-thousandth 

 part of the bulk of the water: ordinary river water gene- 

 ral ly containing one per cent, of oxygen. 



The general colour of the tench is greenish brown, or 

 olive having a golden hue, which latter tint is most con- 

 ipicuous on the under parts of the fish. From the carp 

 it is readily distinguished by the small size of its scales, and 

 also the small extent of the dorsal fin : its form is rather 

 i-c]) in proportion to the length. It spawns usually 

 about the middle of June, and deposits its ova on weeds. 



TINCTURES are solutions of the active principles, 

 mostly af vegetables, sometimes of saline medicines, and 

 more rarely of animal matters, in certain solvents. From 

 possessing more or less of colour, they have obtained this 

 . They are distinguished according to the kind of 

 solvent employed. When alcohol is used, they are termed 



alcoholic tinctures, or more generally simply tinctures, 

 when sulphuric asther is used, they are denominated 

 (ctherial tinctures. When wine is used, though differing 

 little from pure alcohol, the term medicated urines is 

 applied to them ; and when the process of instillation is 

 employed to aid the extraction, particularly of volatile oils, 

 the result is termed a spirit, such as of rosemary. Ammo- 

 nia is sometimes conjoined, and the proceeds termed an 

 ammoniated tincture.' In some cases less of the principal 

 ingredient is taken up or dissolved when ammonia is used, 

 than when simple alcohol is employed, as in the tinctura 

 guaiacum ammoniatum. Formerly some tinctures were 

 called essences, from the term esse, it being thought that 

 they contained only the purer or more refined portion, the 

 alcohol leaving all the baser principles, such as the starch, 

 gum, woody fibre, &c., undissolved : quintessence was a 

 still higher degree of this. These terms are now disused 

 by pharmaceutists, though retained by the people. Elixirs 

 differ only from being of a greater consistence : they are not 

 uni'requently turbid from the extractive matter suspended 

 in them. Tinctures are further distinguished into simple and 

 compound. They are called simple when one substance 

 only is submitted to the solvent ; compound, when two or 

 more are. Another important distinction among tinctures 

 is founded upon the degree of strength of the alcohol em- 

 ployed. Where the active principle is nearly pure resin, 

 a strong spirit is needed ; when much gum is associated 

 with the resin, a weaker is required. Hence some tinc- 

 tures are prepared with proof spirit, as the greater num- 

 ber ; a few with spirit above proof; and some with rec- 

 tified spirit. 



A well-prepared tincture should be clear, possessing the 

 colour of the article which is its base, and partaking in an 

 eminent degree of its characteristic odour and taste. As a 

 general rule, five or six parts of the liquid chosen is to be 

 used for one part of the solid material, which is to be 

 bruised or comminuted before being submitted to macera- 

 tion. The maceration, which should be conducted in 

 well-stopped glass vessels, is generally continued for four- 

 teen days, during which the ingredients are to be frequently 

 shaken, and at the end strained. The pure tincture is 

 then to be preserved in a tightly-stopped bottle, which 

 should be opake, or sheltered from the light. From seve- 

 ral tinctures a deposit falls down, either from some slow 

 chemical change taking place among the ingredients, or 

 from the evaporation of some of the spirit. This renders 

 old tinctures not uni'requently turbid, and of variable 

 strength. Thus tincture of opium When newly prepared 

 contains one grain of opium in nineteen minims, but after 

 some time one grain of opium is contained in only fourteen 

 minims. This inconvenience may be avoided with all 

 recent vegetables, by forming what are termed ' vegetable 

 juices.' These are merely the juices of the fresh plant 

 expressed by a powerful wooden press, and the juice 

 allowed to stand twenty-four hours, during which a copious 

 precipitation of feculent matter takes place, which is 

 further promoted by adding alcohol 56 over proof, in the 

 proportion of four fluid ounces to every sixteen fluid 

 ounces of the juice. After standing for twenty-four hours, 

 the juice is to be filtered through bibulous paper (prepared 

 from wool), when it will keep unimpaired for a length of 

 time. 



These vegetable juices always retain their purity, and 

 are of the same degree of strength at last as at first. By 

 this means not only is the process simplified, and the time 

 required for their preparation greatly abridged, being 

 reduced from fourteen days to two ; but their medicinal 

 efficacy is greater than that of the ordinary tinctures, and, 

 from containing less alcohol, they can be given in cases 

 where the stimulating action of this principle interferes 

 with the effect of the substance dissolved in it, or renders 

 its exhibition improper, as in the case of young children. 



In preparing the officinal spirits, the directions ot the 

 Pharmacopeia are rarely complied with. Most chemists 

 content themselves with dissolving some of the essential 

 oil of the plant in alcohol of the requisite strength, by 

 which much expense and trouble, as well as loss ot time, 

 are sivoidcd. 



(See a pamphlet on The Best Method of Obtaining the 

 Most Puwerful Vegetable Preparations for Medical ( 

 In IMward Bentley.) 



TINDAL, MATTHEW, LL.D., was the son of the Rev. 

 John Tindal, parish clergyman at Beer-Ferres in Devon- 



