4>7& ON USEFUL AND BOOK I. 



Sir John Maxwell Heron informed me, that thirty years ago 

 a barn at Springkell was roofed with larch wood, which is still 

 perfectly fresh. The doors were also made of it, without being 

 painted. Not long after they were made, a substance began 

 to exude from them, which soon covered all their surface and 

 closed up the joints. At present these doors present a brown 

 mass apparently of one piece of wood, and so hard that a mus- 

 ket ball fired against it from a few yards distance does not make 

 the least impression. A similar effect is said to take place with 

 the roofs which are made of deal in North America*. An in- 

 sect, the coccus lariocea, made its appearance on the larch in the 

 northern counties some years ago, and proved very pernicious 

 in several instances. ( The tree has since been too much neg- 

 lected ; but as the plantations injured have now recovered, and 

 are thriving well, it is to be hoped that this tree will soon re- 

 sume its proper place in the estimation of Planters. 



•Pi ' 1 y 



The qualities of the larch suitable for ship-building, as its 

 resistance of fire and decay, its hot being apt to splinter, &c. 

 have been noticed by several writers. The form of the larch, 

 however, is unsuitable for some of the purposes of naval archi- 

 tecture. To render it more suitable, pruning has been recom- 

 mended by some ; and, what is still less practicable, shading 



* See Agricola's Observations on Timber Trees. 



