quired, not as 10 to 15, but in its inverse ratio, as 15 to 10, or 15 10 3 3x1015, or 2; and 2 months is the answer required.

The double rule of three (at least in the class of questions which are usually considered as falling under it) is applied where time is an element in the production which the question supposes. For example: supposing it known that A men can pave B square feet in C days, it may be asked how many men can pave 6 square feet in c days, or how many square feet can a men pave in c days, or how many days will it take a men to pave b square feet. If we write down the data and answer in two lines, and in the following order-force employed-effect produced-time of production-thus,

The principal caution which a beginner requires is ;-not to suppose that the rule of three (or the rule of finding a fourth quantity which, with three others, shall constitute a proportion) is to be applied in all cases in which three quantities are given to find a fourth. That such a caution is necessary arises from the defect of works on arithmetic; which frequently exhibit this rule without any mention of proportion, and leave it to be inferred that there is but one way of obtaining a fourth quantity from three others. THREE RIVERS. [CANADA.]

THRIO THORUS, M. Vieillot's name for a genus of birds, Sylvia, Lath., and placed by Mr. G. R. Gray in his subfamily TROGLODYTINÆ, of his family Certhidæ.

THRIOTHU'RUS, M. Vieillot's name for a genus of Birds (Sylvia, Lath.), placed by Mr. G. R. Gray in his subfamily TROGLODYTINE.

THROCMORTON, SIR NICHOLAS, was descended from an antient family in Warwickshire, and his ancestors had been employed in the higher offices of state for some centuries. His father, Sir George Throcmorton, had been in favour with Henry VIII., but, being a zealous papist, he incurred the king's displeasure by refusing to take the oath of supremacy, and about 1538 was imprisoned in the Tower of London, where he remained several years.

Nicholas, who was Sir George's fourth son, was born about the year 1513. Having been appointed page to the Duke of Richmond, the king's natural son, he accompanied his master to France, and remained in his service till the duke's death in 1536.

Sir George Throcmorton was released from the Tower in 1543. His son Nicholas was then appointed sewer to the king, in which it was his duty to attend the

'marshall'd feast,

Serv'd up in hall with sewer and seneschal.'

In 1544 he headed a troop in the armament against France which Henry VIII. commanded in person; he assisted at the siege of Boulogne, and after his return received a pension from the king as a reward for his services. After the king's death he attached himself to the queendowager Catherine Parr, and to the Princess Elizabeth. In 1547 he distinguished himself in the campaign in Scotland under the Protector Somerset; he was present at the battle of Pinkey (or Musselburgh), and Somerset sent him to London with the news of the victory. He was soon afterwards created a knight, appointed to a place in the privy-chamber, and admitted to great intimacy with Edward VI. The king bestowed upon him some valuable manors, and made him under-treasurer of the Mint. He sat in parliament during Edward's reign as member for Northampton.

A short time before the king's death, Sir Nicholas married the daughter of Sir Nicholas Carew, and on taking his wife to visit his father at Coughton in Warwickshire, he was received with coldness by the old knight; partly perhaps on account of his Protestant principles, but chiefly because he had been knighted before his eldest brother. To remove this cause of offence, he took his brother back with him to court, and, at the request of Sir Nicholas, the king raised him to the dignity of a knight.

Sir Nicholas Throcmorton was present when Edward VI. died at Greenwich in 1553. He was aware of the designs of the partisans of Lady Jane Grey, but, though a Protestant, he was too much attached to law and legitimacy to give the least sanction to them. He therefore came immediately to London, and despatched Mary's goldsmith to announce to her the king's demise.

On the 2nd of February, 1554, Sir Nicholas Throcmorton being concerned in the rebellion of Sir Thomas Wyatt. was arrested and committed to the Tower on a charge of On the 17th of April he was brought to trial at Guildhall, London. This trial is the most important and interesting event in his life. A report of it, taken from Holinshed, is given in the Library of Entertaining Knowledge-Criminal Trials.' It is certain that he was acquainted with Wyatt's intentions, and there is little doubt that he was to some extent implicated in the rebellion. He was tried before commissioners, some of whom were bitterly inimical to him, and who seemed to regard his trial as merely a form necessary to be gone through previous to his execution. Sir Nicholas however conducted his own defence; and this he did with such admirable adroitness, such promptness of reply and coolness of argument, intermixed with retorts, spirited, fearless, and reiterated, in answer to the partial remarks of the lord chief justice and other commissioners, and followed up by an impassioned earnestness of appeal to the jury, that, in defiance of the threats of the chief justice and the attorney-general, he obtained a verdict of acquittal. Sir Nicholas was directed to be discharged, but was remanded, and kept in prison till the 18th Jan., 1555. The jury were made to suffer severely for their independent verdict. Two were fined 20007. each, six were fined 1000 marks each, and four, who expressed contrition, were not fined. All were remanded to prison, where they remained till the 12th of December, when five were discharged on payment of the reduced fine of 2201. each, three on payment of 60%. each, and four without fine.

Sir Nicholas Throcmorton, after his release, avoided the approaching storm of persecution by going to France, where he remained till 1556. Though he afterwards served in Queen Mary's army under the Earl of Pembroke, he devoted himself chiefly to the princess Elizabeth, whom he visited privately at Hatfield. When Queen Mary died, he was admitted to see her corpse, and, as Elizabeth had requested, took from her finger the wedding-ring which had been given to her by Philip, and delivered it to Elizabeth. Elizabeth gave him the office of chief butler of England, a situation of some dignity, but inconsiderable emolument, and afterwards made him chamberlain of the exchequer. In 1559 he was sent on an embassy to France, and remained at the French court as resident ambassador till the beginning of 1563. Dr. Forbes has published the greater part of Throcmorton's correspondence with his own government while he was in this confidential situation. It displays great diplomatic skill and management, but perhaps rather too much tendency to intrigue; and he supported the cautious aud somewhat doubtful policy of Cecil with zeal and discretion. Indeed he was on the most confidential terms with Cecil during the whole of this period, but after his return a coolness arose between the two statesmen, which increased till it became a strong personal animosity.

In 1565 Throcmorton was sent on a special embassy to Scotland, to remonstrate with Mary Queen of Scots against her intended marriage with Darnley; and when Mary was imprisoned at Lochleven in 1567, Throcmorton was commissioned by Elizabeth to negotiate with the rebel lords for her release.

In 1569 Throcmorton was sent to the Tower on a charge, which indeed appears to have been well founded, of having been engaged in the intrigue for a marriage between Mary Queen of Scots and the Duke of Norfolk. Though he was not kept long in confinement, he never afterwards regained the confidence of Elizabeth, and the distress of

·

THROMBUS is a tumour formed by blood effused from a vein after bleeding, and coagulated in the adjacent cellular tissue. It is a kind of intense ecchymosis or bruise, and usually arises from the puncture in the vein not having been made exactly opposite that in the skin, so that some of the blood, instead of flowing out, is infiltrated between the vein and the surface. It is rarely of sufficient importance to require treatment, and is usually removed like the effused blood of an ordinary bruise. Sometimes however inflammation ensues around the tumour, which should be treated by leeches and cold; or, if it proceed to suppuration, should be managed like a common abscess.

THROSTLE. [THRUSHES.]

The only variety of thrush in which the eruption is the most obvious sign of disease is that which is called milkthrush, or aphtha infantum, or sometimes, in the supposition that it is the primary disease, idiopathic thrush. This however is almost always connected with disturbance of the digestion and other functions, and is usually traceable to some error of diet. It is most frequently observed in children that are brought up by hand;' and, in ordinary cases, requires only the means adapted to correct the disturbed digestion, such as small doses of magnesia and gentle purgatives. In very weakly children however, and in those that are ill fed and clothed, the surface of the mouth and fauces, exposed by the bursting of the vesicles, may slough or ulcerate; and this condition is always a sign of the necessity of administering tonics, nutritious food, and even powerful stimulants, such as wine or brandy. It is this form of thrush which is usually described as aphtha maligna.

In adults, thrush is a very common occurrence in the advanced stages of many diseases, such as typhoid and other acute fevers, the hectic fever accompanying phthisis, diabetes, &c. in short, in nearly all cases in which there is great prostration of strength, thrush may occur. In these cases, the only treatment that can be applied peculiarly to it is local. Great relief is often afforded by lightly sponging the affected surfaces with a solution of nitrate of silver, in the proportion of eight or ten grains to an ounce of water. Gargles, consisting of a drachm of alum to a pint of water or acidulated infusion of roses, or of one or two drachms of sub-borate of soda to half a pint of water, are often beneficial; and so is the mel boracis of the Pharmacopoeia, when a small quantity of it is held for a few minutes in contact with the affected

part.

THRUSHES. Under this name many ornithologists treat of the whole of the MERULIDE, in which article the

views of Mr. Vigors, Mr. Swainson, and the Prince of Musignano, now Prince of Canino, with regard to this family, are given.

Since the article Merulide was written, Mr. G. R. Gray has published his List of the Genera of Birds,' and we proceed to lay before our readers his arrangement.

Mr. G. R. Gray makes the Turdidae (Turdus, Linn.) the second family of his third tribe (Dentirostres) of his second order (Passeres). The Dentirostres are placed by him between the Tenuirostres and the Conirostres, and the Turdidae between the Luscinidae and the Muscicapida. The following are the subfamilies and genera into which

Mr. G, R. Gray divides the Turdidæ :

Subfam. 2. Turdinæ. Genera:-Petrocossyphus, Boie; Orocetes, G. R. Gray; Larvivora, Hodgs.; Bessonornis, Smith; Saxicolides, Less.; Chaetops, Sw.; Geocichla, Kuhl; Zoothera, Vig.; Myiophaga, Less.; Oreocincla, Gould; Turdus, Linn.; Merula (Ray), Boie; Mimus, Briss.; Toxostoma, Wagl. Subfam. 3. Timalinæ.

Genera:-Donacobius, Sw.; Pellorneum, Sw.; Aipunemia, Sw.; Crateropus, Sw.; Garrulax, Less.; Actinodura, Gould; Cinelosoma, Vig. and Horsf.; Suya, Hodgs.; Sibia, Hodgs.; Tesia, Hodgs.; Malacocercus, Sw.; Timalia, Horsf.; Pomatorhinus, Horsf.; ·? Paludicola, Hodgs.; Icteria, Vieill.; Turnagra, Less. Subfam. 4. Oriolinæ. Genera:-Dulus, Vieill.; Sphecotheres, Vieill.; Oriolus, Linn.; Mimeta, Vig. and Horsf.; Analcipus, Sw. ; Sericulus, Sw.; Oriolia, J. Geoff.

Subfam. 5. Pycnonotinæ. Genera:-Microscelis, G. R. Gray; Microtarsus, Eyton; Malacopteron, Eyton; Trichophorus, Temm.; Hypsipetes, Vig.; Yuhina, Hodgs.; Phyllastrephus, Sw.; Hamatornis, Sw.; Pycnonotus, Kuhl; Andropadus, Sw.;? Trichixos, Less.;? Setornis, Less.

Mr. G. R. Gray, with his usual diligence and accuracy, gives the synonyms of all these genera; and observes, with regard to some of them, that Drymophila, Sw., has been used in botany; that Leptorhynchus, Menestr., was previously employed; Petrophila, Sw., used in botany; Cossypha, Vig., used in entomology, only the termination is there in us; Cichla, Wagl., previously used in ichthyology; Paludicola, Hodgs., previously employed in herpetology; and Micropus, and Brachypus, Sw., previously used in other branches of natural history.

Some of these forms have already been noticed in detail in this work, and we shall here confine ourselves to the true thrushes, or those so nearly allied to them, that, in common parlance, they are so termed. EUROPEAN THRUSHES.

The following thrushes are European:

Black Ouzel, or BLACKBIRD, Merula vulgaris, Ray; the Ring Ouzel, Merula torquata, Briss.; the Migratory Ouzel, Merula migratoria, Sw.; the Black-throated Thrush, Turdus atrogularis, Temm.; the Fieldfare, Turdus pilaris, Linn.; the Redwing, Turdus Iliacus, Linn.; the Missel Thrush, Turdus viscivorus, Linn.; the SongThrush, or Throstle, Turdus musicus, Linn.; Naumann's Thrush, Turdus Naumanni, Temm.; the Pallid Thrush, Turdus pallidus, Pall.; White's Thrush, Turdus Whilei, Eyton; the Siberian Thrush, Turdus Sibericus, Pall.; the Water Ouzel, or Common Dipper, Cinclus aquaticus, Bechst.; the Black-bellied Water-Ouzel, Cinclus melano gaster, Brehm; Pallas's Water Ouzel, Cinclus Pallasi, Temm.; the Rock-Thrush, Petrocincla saxatilis, Vig.; and the Blue-Thrush, Petrocincla cyaneus, Vig.

Of these, the WATER OUZEL, or Common Dipper; the Missel Thrush; White's Thrush (occasional only); the Song Thrush; the Fieldfare; the Redwing; the Blackbird; and the Ring Ouzel, or RING BLACKBIRD, are British.

We select as an example the sweetest songster among this tribe, in our opinion at least, and we write it without disrespect to the rich mellow whistle of the blackbird, or the loud stirring notes of the missel thrush.

The Throstle or Song Thrush.

This well-known bird needs no description. It is the mune, and Tordo Bottaccio of the Italians; Sing-drossel, Grive and Petite Grive of the French; Tordo, Tordo comAderyn or Weiss-drossel, of the Germans; Mavis, with the other

bronfraith of the antient British.
Geographical Distribution.-Inhabits every country in
Europe, haunting gardens and woods near streams or mes-

• N.B. The Mauvis of the French is the Redwing.

dows. Bechstein says that in Germany, as soon as the autumnal fogs appear, the throstles collect in large flights to seek a warmer climate, the principal time of passage being from the 15th of Sept. to the 15th of October, and the return about the middle or end of March, when each pair seeks its own district. In Britain it is permanent, and spread over England, Wales, Ireland, Scotland, and its islands. Russia, Denmark, Sweden, and Norway possess it. In the south, besides Germany, France, Italy, and Greece have it. It has been seen in winter at Smyrna and Trebizond. Professor Nilsson states that it leaves Sweden for the winter, and comes farther south. Mr. Selby observes that such visitors arrive in Britain with a north or north-east wind, and, after staying a few days to recruit, move southward.

Habits, Food, &c.-Worms, insects, snails, and fruits form the food of the throstle. The common garden-snail, Helix hortensis, and the wood-snail, Helix nemoralis, are killed and eaten in great numbers by this species. The bird beats and breaks the shells against a stone to get at the animals. The nest is made of green moss generally, and fine root-fibres on the outside, and is lined within with cow-dung and decayed wood, the lining forming a cement, so perfectly spread that it will hold water. Eggs four or five, of a light blue, the larger end having a few small black specks or spots. Time of incubation thirteen days. The first hatch generally comes forth in April, but the young have been known to be out at the end of March. There are generally two broods in the year. Both the cock and the hen sit, but the former less than the latter. He often feeds her on the nest. A holly, a thick bush-a tall one is mostly preferred-a dense and somewhat high shrub or a fir, is usually selected; but the bird has been known to breed in an open shed or tool-house, and does not seem to shun the neighbourhood of man. In 1833 a pair built their nest in a low tree at the bottom of Gray's Inn Gardens, near the gates where passengers are going by all day long. The hen laid her complement of eggs, and was sitting on them, when a cat climbed up and killed her on the nest. The cock immediately deserted the place. Bechstein states that in captivity the Throstle is easily taught to perform airs. For taking it he recommends perch with a limed twig as the best mode of capturing a fine-toned male: but in September or October he says that they may be caught in the water-traps, where they repair at sunrise and sunset, so late that they sometimes cannot be seen, and the bird-catcher is only guided by his ear. He observes that, when the birds enter the water, there must be no haste on the part of the fowler, because they like to bathe in company, and assemble sometimes to the number of ten or twelve at once, by means of a peculiar call. Bechstein tells us that the first which finds a convenient stream, and wishes to go to it, cries in a tone of surprise or joy, sik, sik, sik, siki, tsac, tsac, tsac: then all the thrushes in the neighbourhood immediately reply in concert and repair to the place. The bath is entered however with a good deal of circumspection on their parts, and they seldom venture till they have seen a Red-breast bathe without danger. But the first that bathes is soon followed by others, and they begin to quarrel among themselves if the bath is not large enough to accommodate all satisfactorily. Bechstein further remarks that it is a good plan to have a tame bird running and fluttering on the banks of the stream, as a decoy to attract them.

ASIATIC THRUSHES.

Example, Turdus erythrogaster.

a

Description.-Male.-Grey-cærulescent above; the cheeks, the sides of the neck, and the quills black; breast, abdomen, and rump red; beak and tarsi black.

Female differs in being cærulescent-brown, the lower part of the back obscurely banded with brown; neck in front whitish marked with dark brown; breast, abdomen, and rump reddish-white marked with undulations. Length 84 inches.

Mr. Gould (Century of Birds from the Himalaya Mountains) states that this beautiful species exhibits a marked departure in the style of colouring from its more typical congeners; and were it not that its form dictated the situation in which it is retained, it would otherwise seem to be allied in many respects to the genus Petrocincla. Locality-The rocky districts of Himalaya; never found in the low lands.

130

Turdus erythrogaster, male and female. (Gould.> AFRICAN THRUSHES.

Example, Turdus strepitans, Smith (Merula Letsitsi. rupa of the same).

Description.-Male.-Front and top of head brownishgrey; occiput, upper aspect of neck, interscapulars, scapulars, and shoulders deep yellowish-grey, faintly shaded with brown; back, rump, and upper tail-coverts dirty ashgrey. Under parts white, tinted in places with ochreyellow; sides of the neck, whole of the breast, flanks, and belly variegated with blackish-brown pyriform spots, one on each feather, the large end reaching nearly to its point. Sides of the head white, slightly tinted with ochre-yellow, variegated below the eyes with three blackish-brown bands; the foremost proceeds from the base of the lower mandible, the second from the middle of the under eyelid, and the third from the outer angle of the eye; the first extends nearly horizontally, and the two others obliquely downwards and backwards till they unite with the horizontal one. Primary wing-coverts and primary quillfeathers deep brownish-red, the latter tipped and edged externally with yellowish-white; the first two-thirds att least of the inner vanes of these feathers are of a clear buff-colour, darkest towards the shafts; secondary wingcoverts and secondary and tertiary quill-feathers dark greyish-brown, the outer vanes lightest, all margined externally and tipped with dirty white. Eyes reddish brown; upper mandible and tip of lower inferiorly as well as the claws liver-brown; lower mandible elsewhere, and the cutting edge of upper, pale saffron-yellow. Feet and in-. sides of the bill deep straw-yellow.

Figure robust and rather short. Bill long, and mode rately strong; upper mandible broad and slightly depressed towards the base, narrow and distinctly notched near the tip; culmen between nostrils elevated and rounded, towards the point of the bill strongly curved; nasal fossæ large and membranous, the nostrils narrow longi-. tudinal slits near to the edges of the mandible; wings short. and rounded, and when folded they reach over the first half of the tail; the first quill-feather rudimentary, the third rather the longest; the second and fourth of equal length, and scarcely shorter than the third; the fifth a little shorter than the fourth, and the remaining primaries diminish in length successively. Tail short and slightly forked. Legs long, tarsi robust, anteriorly indistinctly scutellated, posteriorly entire; toes strong, the inner and outer toes of the same length; claws strong, much curved and pointed. Length from point of bill to tip of tail eight inches six lines