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•f the Royal Society, and in France, under that of the Tnslitufe. After having beetl 
carried o« for soine time, 'he observers, either etnbarrassed with the dilliculty of he 
enquiry, or exhausled by tüe labour atlendiog it, abamJoned their underlaking, before 
they obiained suflicient data lo form the basis of any satisfactory invealigaiion. Mr. 
Whewell directed the receni enquires io two distinct objeets ; first, to aseertain Ute 
bäte at'whinh the great tidal wave moves, and secondly, the Position of high and iow 
watet ; or in ollier words, the actual heigbl of the tide wave al different places. Duriog 
the last fevv years, observalions were made by the coast guard ou the coasts of the 
United ii ngdom, and returns have been obiained from more than live hundred pl.ices. 
Effjrts liave also been made, through the intervention of the various euibassies, to 
oblain like ioformation from other countries; and these requests have been every 
where met with thai liberal spirit, w < ich so happily charactenses the present titnes. 
Riissm, Sweden, ümma k, Holland, France, Spain, and the United Stales, have all 
joioed in this initresting laboin. By such means, we shall no doubl, have before us 
a tolerably correct description of the tidal phenomena in every pari of the globe ; theu, 
and not tili then, shall we be in a position lo enable us to apply the powers of iheory 
to the solulion of these phenomena, Mr. Whewell has however, made soine first 
essays towards the solulion of the problem, which possesses great interest and which 
thiovva stronglight upoo the dilliculties, with which the enquiry has beeil surrounded. 
From what has been stated, it will be easily perceived, that, in an extensive ocean, 
uninterrupted and unbroken by the shores of conlinents and islands, the «Greai ffde 
Wave» would move with a slow and regulär motion round the globe, from the East 
to the West, its point of oreatest heiglil being at ihose parts of the earth, at wliich 
th< moun ii as been vertical. that is to points belween tlie Tropics Let us theu, in 
the lirst place, imagine such a wave conlinually flowing round the earth in the 
iniervat of time, which, e'apses between two successive southings of the mooii ; tliis is 
what Mr. Whewell Calls the « Primary Tioe, * and whalever coasts would be exposed 
teil, would liave their tidal phenomena as nearly coincident wiili ihe immediute 
results of iheory as possible, But let us suppose this great «tide wave» lo pass 
along a shore, running direct from East lo West, so that the lenciii of the wave 
would be at right angies to i he dire’Tion of the coast, and the directon of its motion 
paralled to Ute coast, Every one, who has seen the effect of waves produced by a 
stone thrown iriio a pond, will comprehend, that the extremily of the tide wave 
abiitting tipon the coast just mentioned, will be field back, and the wave itself, 
instea f of exlending in a str dghl iine North and South, will be bent tntoa curve near 
tue coast, and will bei ly forwards towards the West. The effect, therefore, of tlie 
coast will, in this case, be, to hold back tlie tide wave, and to cause the time of high 
water lo be earlier at the severai points of that coast, than it would be if ihis effect 
were not produced upon ihe foim of the tide wave. Here then, is obvjonsiy auother 
cause for tlie disagreeinent of the actual tidal phenomena, with what would seem to 
be the immediale results iheory. 
But again, let us suppose this coast so running, West and East, to have a large 
inlet of tlie sea at some pari of it, running North and South. As the great tide- wave 
passe« ihe niouth of tliis inlet, it will propagate a wave from the mouih to its head, 
wliich wave will, in fact, be a continuation or part of tlie great lide-wave itself, driven 
up the inlet as the wave passes its momh. Tliis, which Mr. W lewell calls the 
«Secondary Tide- W ave » will proceed up the inlet from South to North, while ihe 
prim. uv tide wave, from wliich it has emanaled, holds on its regulär course from 
Ea.l lo West. It is clear, then, thit the tide in the inlet, which corresponds with 
tlie great tide-wave which has just passed on, will necessarily occur ata very different 
time from that of tlie primary tide; they have separuled, and one moves along the 
merulian, while the ollier is iransferred from meridian to meridian towards the West. 
The primary tide inay, therefore, occur at one hour, while tlie corresponding secondary 
tide may have occurred severai hours before. 
M. J Morris ent re eibuite datts de grands developpemens stir 
le fl n x et le relhix de la vague pcndant la roaree ; stir 1’origine 
des courants contraires ou remoux ; sur la marche du courant 
e<)uatorial tpii semhle etre un grand Heuve traversant l’ocean de 
l>Est a l’Ouest et termiue en ces mot s son travail: 
