T I D 



TH'O'X/I. STK'KANO, Lorn in 17<'.i in theVal Sawina, 

 in Hi. studied at Milan, and aftei 



at Pa 



pointed in. untry parish n. : m his 



mitiv. When tlie Kreiu-li invaded I.ombardy in 



lie nnd his brother Cesaic F. ;io was an 



ndvo . il tin- revolutionary movement : but when 



ime back in IT'.l'.l. Tun//! .-d to 



emigrate into F;;ricc, and his brother 



ti to ('attain. Ticozzi returned with thcvic- 



- French in the following M-ar. and was Upointed to 



:l political offices under the Italian republic, and in 



IS Hi was : .elect ot'the department of the I'iaM- 



nude: N n. In Isld he published 



i monastic, institutions: Degli Is- 



tituti Olaustrali Dialoghi Tn-.' SMI., Hcllnno. He lost his 

 situation on the tall of Napoleon, and retired to Milan, 

 where he lived mainly In literary labour. He tiiinslated 

 into Italian Sisniondi's ' History pf the Italian Republics,' 

 LJorente's 'History of the Inquisition,' Agineourt's History 

 ol' the Arts,' and other works. In 1H1K he published his 



Di/ionario dei Pittori dal Rinnovamento dclie Arti fino al 



which he afterwards merged in his larger work, 

 iiiario dcgli Architelti. Scultori, Pittori, Intagliatori 

 in ranic e in pietra, t'oniatori di Mcdaglie, Musaieisti, 

 Niellatori, Intarsiatori d'ogni Kta e d'ogni Na/.ione,' Milan, 

 -. s\o. This i> a really useful compilation, although 

 not always exact about dates. He also published 1, 

 ' Memone Storiehe,' Florence, 1'* vols. 8vo., being a scries 

 of historical tales taken from the history of Italy in the 

 middle ages; 2, 'Viaggi di Messer Francesco Novello da 

 ( 'air;; di Padova. e di Taddea d'Kste, sua consortc, 



n diverge parti d'Europa.' J -.. a work also ill 



tive of the same period ; 3, a continuation of Corniani's 

 biographical work, ' I Secoli della Lctteratura Italiana.' 

 down to our own times, and also a continuation of li. 

 collection of letters concerning the arts : ' Haccolta di Let- 

 ten- sulla Pittura. Scultura, cd Arehitettura, scritti dai pid 

 celebri Pcrsonaggi dei Secoli \\.. xvi.. e xvii.. eontinuata 

 lino ad nostri Giorni.' H vols. Kvo. ; and likewise a con- 

 tinuation ol'Vcni's -History of Milan:' ' Storia di Milano 

 del < 'onto Pietro Verri, dai suoi piu rimotiTempi fino al l.")2.~>. 

 eontinuata tino alia presente Kta,' Milan, vols. 12mo., 

 besides several dissertations upon various paintings and 

 other minor works. He left medited and unfinished a 

 \ ! foe on the Art of distin- 

 guishing Copies from the Originals in Painting.' 



Ticozzi died in IKki. He married a granddaughter of 

 the historian Giannone, by whom he had several children. 

 . Hinynijin </!'i'/i lt<ili<uii lllustri.} 



T1DF.-MII.L. a kind of water-mill in which the ma- 

 ehineiy is im]>elled by the alternate flow and ebb of the 

 title, instead of a stream continually flowing in one direc- 

 tion and at a nearly uniform level. Although tide-mills 

 ha\e never been brought into very common use in this or 

 in other countries, they arc by no means of recent origin. 

 Hcckmann. in his History of Inventions ' < : English edition 

 of 1H14, vol. i.. p. il.V, states that ' at Venice and other 

 places there were mills which righted themselves by ebb- 

 nnl flowing of the tide, anil which CM-IT six hours 

 chanced the position of the wheels;' and he adds that 



/anctti h;ts shown, from some old charters, that such 

 mills e\i-ted about the year KM I. and with still more ccr- 



1070. MM 1107.' Helidor, ill his 'Architcc- 



i-iliquc.' d- 'de-mill which W;LS used at 



Dunl, y in the last century, and attributes the in- 



arpcnter of that place, named i 



The expense attending the constniction of tide-mills ren- 

 'licir adoption (inadvisable in ordinary cases : but in 

 many situations in which other mills are Inapplicable, 

 owing to the want of a sufficient current, or the ne. 

 of avoiding any in'- with the na\igation 



iv be erected with advantage. The water 

 required for impelling their machinery may be admitted 

 either from the side of a tidal liver or immc.; 

 the sea. 



Tlie late T)r. Gregory, in the second volume of his 

 ' Treatise on Mechanics.' has devoted several pages to an 

 account of various plans for obtaining a moving-pou. r 

 i. '.MI the rising and falling of the tide ; and. although he 

 doe* not pretend to notice all the contrivances which have 

 been proponed for the purpose, he divides the most im- 



T I D 



portant into four classes, varying from each other in the 

 manner in which the motion of the water--.- 

 and applied to the machinery of the null. In 



he wheel turns in < 



rising, and in the opposite direction while it tails; in the 

 second the passage of the water is so regulated by si 

 that the wheel may always turn in one direction ; in the 

 third the wheel itself rises and falls with the tin 



ve a tolerably equal degree of immersion, or a uni- 

 form head of water to act upon its float-hoards : an.l in 

 the fourth the axle of the wheel is permanently 1i\ 

 one level, and the wheel is so constructed as to revolve 

 whether partially or completely immersed in the v. 

 Of these conditions it , ed that the first and third 



have been usually exemplified in one machine, and that 

 the second and fourth may icadilv be united in another. 

 Dr. Gregory therefore treats u f tide-nulls under two 

 heads, which are as follow : 1. Tide-mills in which the 

 water-wheel rises and falls, and turns one way with flu- 

 rising tide, and the contrary when it ebbs: and. 'J. Tide- 

 mills in which the axle of' the water-wheel neithei 

 nor falls, and in which that wheel is made always t 

 volve in the same direction. 



Of the first of these v arieties of tide-mill a good example 

 is given from acorn-mill erected on the hank of the Thames. 

 -t Greenwich, by Mr. Lloyd. Tin- details of the me- 

 chanism are fully explained by Gregory, and al- 

 fessor Barlow, in his 'Treatise on Manufactures and 

 chinery' in the ' Encyclopedia Metropolitana :' but flu- 

 essential features of the contrivance may be briefly de- 

 scribed. The side of the mill which is parallel to the 

 river is forty feet wide, and is capable of being opened to 

 the river by shuce-galcs which are carried down to low- 

 water mark". Thus there is a water-way forty feet wide 

 through the mill, bv which the rising tide cnl> 

 voir, which covers about four acres of land. A smaller 

 reservoir beyond the principal one affords the means for 

 cleansing the whole apparatus by flushing or scoun 

 low-water. The water-wheel is a cylinder twenty-si v 

 long and eleven feet in diameter, with thirty-two float- 

 's, arranged in four divisions on the same priiicr, 

 the divided paddle-wheel described under STKAM-\' 

 vol. xxii., p. f><)9. in order to equalize the action of the 

 water: and its axis is laid in a position parallel to the side 

 of the river, so that it may be turned with equal facility by 



in flowing from the river into the reservoir, or 

 the reservoir into the river, according to the direction in 

 which the tide is moving, and the positions of : 

 for admitting the head of water on one side, and al'.i 

 free vent for the tail-water on the other. At each end of 

 the water-wheel is fixed, upon the same axis, a large 

 bevil-wheel, from which the rotatory motion is communi- 

 cated to an upright shaft, bv means of two small hori- 

 zontal bevil-whcels. called wallowcrs, either of which may 

 he readily thrown into connection with the large wheel, 

 while the other revolves freely, without coming in contact 

 with it. Thus, by throwing the upper wallower into 

 while the water-wheel icvolvcs in one direction, and t In- 

 lower one when its motion is reversed, the vertical si 

 m:ulc to revolve continually in one direction. The v. 

 wheel, and the parts immediately connected with it, form- 

 ing an apparatus of the weight of nearly twenty Ion- 

 go mounted as to rise and fall by the action of tin- water, 

 with very little attention: the bottom of the whccl-i. 

 being connected with a kind of horizontal folding-door, 

 which prevents any communication between tl>. 

 the re ecpting in the required direction, wh,; 



maybe the position of the wheel-frame. The moti. 

 the vertical shafts is communicated to the machinery of 

 the mill by large horizontal wheels which turn with the 

 but do not rise and fall with them. The weight of 

 upportcd by a 'ion- 



rollers resting upon a stationary part of tli 

 that the vertical shafts, which are squared to fit the i 

 may slide freely up and down, although they cannot turn 

 round without turning the wheels. 



Of the means for effecting the objects required in flu- 

 second of the above-i 'ii-s of tide-nu- 



light notice will suffice. Helidor describes a water- 

 wheel contrived by MM. Go-set and DC hi Deliille. in 

 which the float hinged in such a manner tha-t, 



while at Ihe bottom of the wheel, they would press against 



