164 TEREDINID^. 



Ovid^s * Tristium/ with tlie alteration of a single word, 

 will tersely express the difficulty of getting rid of it. 



" ^Egrius ejicitur, quam non admittitur hospes." 



A very slight coating of any kind, applied to the sur- 

 face of the wood, will suffice to keep out the infant 

 burglar. Tar would answer the purpose ; but this 

 is liable to be accidentally rubbed off, or removed by 

 the continued agitation of the waves. Sir Gardner 

 Wilkinson informs us that the ancient Egyptians glazed 

 some of their inscriptions on stone, by covering them 

 with a vitrifiable composition, which was exposed to a 

 certain degree of heat, until properly melted and diffused 

 over the surface. Perhaps wood cannot be treated in 

 the same way ; but a liquid mixture, containing the re- 

 quisite ingredients, and capable of penetrating its pores 

 or fibrous texture, might be invented and applied to a 

 pile or the hull of a vessel. Any mineral preparation 

 that shall adhere firmly and permanently to the wood, 

 and not be subject to external influences, must be effi- 

 cacious. Such may be the silicate of lime, invented by 

 the late Mr. Ransome, and used for coating stone- work. 

 Every chemist knows that this is a manifest improve- 

 ment on Kuhlmann's process, which consists of liquid 

 silicate of potash or " water-glass." Szerelmey pro- 

 posed an additional wash of a soluble bitumen, and 

 called the preparation " Silicat-Zopissa " ; but his ex- 

 periment has not yet been adequately tested. Zopissa 

 appears to have been a mixture of pitch and wax, first 

 used by the Phoenicians and Egyptians, and afterwards 

 by the Greeks and Romans, to preserve their merchant 

 vessels and men of war. The preparations of Ransome 

 and Szerelmey were tried in 1860 on part of the stone 

 facing of our Houses of Parliament, which had suffered 



