128 THE BELL SYSTEM TECHNICAL JOURNAL, JANUARY 1953 



can be evaluated as wood preservatives by mixing the toxic substances 

 with a malt extract agar solution and then testing the mix against 

 standard fungi." 



Flerov and Popov had used sand in their preliminary experiments, but 

 they were by no means the first to do so (see Falck^^). Rabanus^^ had 

 reported his experiments with sand-block cultures two years earlier. He 

 placed a pair of wood blocks — one treated and one untreated — on glass 

 rods on wet sand in Erlenmeyer flasks; and after sterilization he inocu- 

 lated the blocks directly with his test fungi. He points out that in this 

 procedure the conditions were less favorable for the fungi than when the 

 treated wood is placed above or on a vigorously growing culture, as in 

 the agar-block test. 



Since the papers by Rabanus and by Flerov and Popov appeared in 

 the same journal, one can assume that the latter knew of Rabanus' work. 

 How much any of them knew of still earlier work by Breazzano is un- 

 certain. His work in Italy,^^' ^^' ^^' ^^ begun in the first decade of the 

 century, is evidence of the intense interest of the management of the 

 Italian railroads in some practical laboratory means for testing wood 

 preservatives that would provide results sooner and with more definite- 

 ness than the traditional service tests. Parts of Breazzano's report of 

 Oct. 9, 1913 are worth quoting in full from the EngHsh translation as 

 historical background information. He reviews the situation as he sees 

 it, and says: 



''New systems and various substances for injection into wood are 

 constantly being put on the market by industrial concerns, so that the 

 Railway Administration finds itself confronted by an ever increasing 

 number of processes to be examined and tested for efficiency." 



By 1910 the Railway Experimental Institute 



"... is well on the way toward testing the efficacy of a system of 

 wood preservation by a method which gives dependable results even 

 after a few months of observation. 



"... after making use also of the advice on the subject received 

 directly from Prof. Tubeuf and from Netzsch's laboratory . . . positive 

 results were obtained with the following technique: 



"On the bottom of an Erlenmeyer flask of 200 ml capacity was placed 

 a thin layer of sand." After sterilization in dry heat at 180°C "sterihzed 

 water was poured on the sand to moisten it well. Then there was placed 

 on the sand the sample of wood, of dimensions about 9x2x1 cm., with 

 one end resting on the damp sand and the other on the inside wall of the 

 flask." 



The whole setup was sterilized in an autoclave at 120°C for about 20 



