EVALUATION OF WOOD PRESERVATIVES 127 



preservation was concerned — was a strong stimulant toward the Lab- 

 oratories' development of a block test, referred to later. It was more or 

 less general information at the time that agar toximetric tests with native 

 and European strains of test fungi were being run in other laboratories 

 in this country; but again — as far as the writer knows — the results 

 were not published. 



In the meantime, and, as in the case of the Rabanus article cited 

 above, before the publication of the Liese^^ report, Flerov and Popov^* 

 published in 1933 in German the basic general principles of a soil-block 

 test. The significance of the article by these two Russian investigators 

 was apparently completely lost on American workers until the publica- 

 tion in England in 1946 of Cartwright and Findlay's ''Decay of Timber 

 and its Prevention. "^^ Findlay had been a member of the Berlin con- 

 ference. Flerov and Popov were familiar with the discussions and result 

 of the conference, and decided in favor of the soil base for their cultures 

 after a critical review of the various methods then in use. Their proposals 

 to all intents and purposes were unknown here. 



Van den Berge's comprehensive thesis"^ on "Testing the Suitability 

 of Fungicides for Wood Preservation" appeared in Dutch in 1934. A 

 mimeographed English translation was made available soon after for 

 limited distribution. European workers were about ready to confine the 

 use of the agar toximetric test to determining relative toxicities only of 

 various preservatives in an agar medium. Liese and his colleagues sum- 

 marized the arguments and experiments on the agar-block method in 

 1935, and launched it into a status of general acceptance in Europe and 

 Great Britain. The British^^' ^' and German^^ editions of the standard 

 were issued in 1939. The Rumanian version"" — closely following the 

 German — came out in 1950. Jacquiot,^^ Lutz^^ and AUiot^ worked out 

 proposals for standard procedures that would be more, comprehensive 

 and in their opinion better applicable to wood preservation research in 

 France. 



The Petri dish — and later the stoppered Erlenmeyer flask — agar 

 methods continued to be used by many American investigators for test- 

 ing wood preservatives, and there is no denying a certain utility in these 

 methods for developing information about fungus poisons. The persist- 

 ency of the agar techniques can be traced through publications by 

 Richards,"" Schmitz,'"' '°' Snell and Shipley,'"' Schmitz, ^ Buckman and 

 von Schrenk,'"^ Schmitz, von Schrenk and Kammerer,'"' Bland'" and 

 Hatfield. ^^ Baechler still uses the closed flask-agar method and the fungus 

 called Madison 517 for determining basic toximetric values;*' ^ and Fin- 

 holt'^ has recently been bold enough to state that 'Tungitoxic materials 



