THE ENTOMOLOGIST. 369 



in danger of falling ; and, in like manner, the piles supporting 

 the Trinity chain-pier, at Leith, were — in 1825, four years 

 only after its erection — so perforated as to be useless, and 

 were removed at a great expense, and replaced by new ones : 

 the girth of the original timbers was forty-eight inches, 

 which, before removal, was reduced to six inches. Various 

 plans for remedying the mischief were tried, but none 

 succeeded so well as covering the whole surface of the 

 timber, from the bottom of the sea to within a foot or two of 

 mean high-water mark, with broad-headed iron nails, techni- 

 cally called scupper nails, set close together. A piece of 

 wood, covered on three of its sides with these nails, was 

 found to have the whole interior eaten away, such portion of 

 the exterior only being left as had been penetrated by the 

 nails. This plan was adopted, at an expense of about i^'lOOO, 

 in the Leith pier, which had cost £30,000 ; and, after four 

 years, it was ascertained that none of the piles thus protected 

 had been penetrated by the Limnoria. Timber used for 

 partially-submerged structures is now generally kyanized, 

 and this process greiatly retards, if it does not totally prevent, 

 the injury occasioned by this insect. The third, and most 

 formidable timber-borer, is the Teredo, the character of which 

 truly curious animal seems to have been as familiar to the 

 ancients as to ourselves. Ovid compares this insidious enemy 

 to the corroding effects of care on man, — 



*' Estur ut occulta vitiata teredine navis ; " 



the simile is as good as the description of the Teredo is 

 perfect. The interest in this mollusk has been kept up to the 

 present hour, and it has been made the subject of three most 

 elaborate and learned treatises in one year, 1833 : they were 

 by Pierre Massuet, Jean Rousset and Godfrey Sellius, the 

 last of whom wrote a quarto volume of three hundred and 

 sixty pages, and cites the labours of two hundred previous 

 authors. Three years previously to the publication of this 

 elaborate work, the Teredo threatened to submerge Holland, 

 and hence the intense interest taken in its history. Holland 

 seems to have been considered, at that period, a country 

 standing on piles ; and it is not astonishing that when the 

 piles were found to be giving way a panic should have set 

 in. It is rather remarkable that the three greatest historians 



