transverse spurs have been adopted to lessen this action but their effect is hardly noticeable. As failure of a groyne will probably cause erosion of the foot of an embankment and a slip, a cheap and effective means, attested by the experience of nearly half a century, of preserving the timber from the attacks of most marine worms may here be named. It consists in scorching the piles, thus preventing fermentation of the sap, and immediately tarring them: also in placing the wood in the opposite direction to that in which it grew; the latter operation has been found to increase the durability 50 per cent., the reason, it is believed, being that the capillary tubes in the trees are so adjusted as to oppose the rising of moisture when the wood is inverted. In excavating for an enclosure embankment, the earth should not be disturbed nearer than is economically necessary, and a cess should be left of about 40 to 50 feet in loose permeable soil, the width being governed by the character of the earth, the depth of the excavation, and the height of the embankment. Should dredging have to be executed near an embankment, a considerable distance should be left between the toe of the slope and the line of operations. Before commencing an estuary or enclosure embankment, it is advisable to notice whether a deposit is left upon the shore by the incoming tide, and to ascertain whether it forms in some degree a protective covering, for if this should be the case, any increase of the velocity of the flowing water which might be caused by dredging or a concentration of the littoral currents should be avoided, or the tidal matter in a state of suspension will not gradually sink to the ground. The tidal deposit, although the earth forming the embankment should not be tipped upon it, may also be of importance as tending to prevent or lessen any percolation of water through the foreshore and under the seat of an embankment; for instance, on the Nile, the deposited slime is found to make a practically watertight covering on the loose sand. Mr. Thomas Stevenson has also stated that, according to the depth below the surface of low water that mud reposes, may be approximately judged the force of wave disturbance and degree of exposure; the less the depth, the less the power possessed by the waves. In the case of treacherous soil which circumstances compelled to be partly used in a reclamation embankment of moderate height, but which it was found would gradually become firm by compression, rough sheet piles with a plank at top have been inserted, giving the outline of the finished slope of the material to be afterwards tipped upon it, the piles and planking not being removed, and, therefore, affording the required temporary support before the earth became consolidated and stable by compression and time.