NOTES AND COMMENTS 931 



Rot IX Structures 



There has been much agitation in recent years in New England in 

 regard to the use of wood in factory construction. For many years 

 southern yellow pine was extensively used in "slow-burning construc- 

 tion," but recently, because of the many failures of structures, owing 

 to the unsuitable character of timber furnished, wood fell into dis- 

 favor. Much to the detriment of the lumber industry, the impression 

 was created that suitable wood for factory construction was no longer 

 available. 



Fred J. Hoxie, Insurance Engineer and Special Inspector with the 

 Inspection Department of the New England Factory Mutual Insurance 

 Company, started an investigation a few years ago to determine the 

 facts in the case, with the result, as recently announced, that the main 

 trouble was due not to scarcity of suitable material, but rather to in- 

 ferior material furnished. In this connection a recent statement of 

 Mr. Hoxie is of interest: 



"Within the last five years I have known of 58 serious cases of rot in 

 mill timber, not including 30 or 40 fire-doors. Of these cases, 32 were 

 roofs of buildings with high humidities, 13 were floors over basements 

 with high humidities, five of the most spectacular cases were caused by 

 new lumber of poor quality deeply infected with living fungus when 

 put into the mill, four were from water constantly dripping on good 

 timber, and four were rot which had occurred several years previous 

 to the time of discovery, and doubtless was caused by fungus brought 

 in the new lumber ; but the drying of the building had killed the fungus 

 and stopped the rot. 



"In every case the damage was preventable. The preventative 

 methods to be used would vary somewhat with conditions. In many 

 cases a better grade of lumber would not have rotted; in other cases 

 where there was more moisture chemically treated lumber would have 

 been necessary. In other cases a slight increase in the temperature 

 would have been the most practicable remedy, as this would have kept 

 the lumber above the dew point and thereby prevented rotting. A 

 water-proof covering over beams which were rotted by water dripping 

 on them would prove efiicient. 



"Three varieties of fungi are responsible for by far the greater part 

 of rotting roofs, and of these the Lensites separia is most frequently 

 found in roof plank. This is also occasionally found in basements; 

 but another of the roof-rotting fungi, the Trametes serialis, is more 

 frequently found in basements. The Merulius lachrymans, Coniophora, 



