{ 462 ) 



In the upper point /"* the compound })asses into the liquid state, 

 heat being absorbed. This absorption consists of two parts, the ordinary 

 lieat of fusion and tlie heat evolved when a part of the liquid (endo- 

 thei-mic) compound decomposes until the equilibrium in the liquid is 

 reached. An at higher temperatures the quantity of the compound in 

 the li(piid is hirge, tlie second quantity of heat will be small in 

 comparison with the tirst and the meliing will cause absorption 

 of heat. 



At Q it is, however, just the reverse because at a low tempera- 

 ture there exists but little compound in the liquid and the dissocia- 

 tion of a large proportion of the liquid compound may evolute so 

 much heat that this exceeds the actual heat of fusion of the 

 solid compound. The total fusion therefore produces heat and con- 

 sequently the liquid field is situated l)elo\v Q. 



Up to the present, however, no endothermic compounds are known 

 in the liquid state. 



Microbiology. — Professor Beijerinck presents a paper from himself 

 and Mr. A. VAN Delden : "(>/^ the bacteria which are active in 

 flax-rotting" . 



(Communicated in the meeting of December 19, 1903). 

 1. How far flax-rotting should go. 



The object of flax-rotting is the partly solving and softening of the 

 rind of the flax-stalk to remove the pectose, in consequence of which 

 the bast-bundles are freed so that later, after drying, the fibres may 

 easil}' be separated from the wood by breaking and scutching. 

 Pectose (/>/ Fig. 1) is the substance of which the young cell-walls 

 consist, as also the outer layers of the old cell-walls; these walls are 

 further built up from cellulose, which in a good rotting does not 

 undergo any change^). 



By the rotting also the middle-lamellae, by which the fibres in the 

 bast-bundles stick together, may go into solution and consequently 

 the bast-bundles would be decomposed into the fibres proper. This is 

 not desirable as in this case no large coherent "lints" would be got 

 in scutching, but only loose fibres, of about 2 cm. in length. 



The fibres of the bast-bundles, however, separate with much greater 



1) For the microbes which affect tlie cellulose proper see Omeljansky, Centralb. 

 f. Bacteriol. 2 Abt. Bd. 8 p. 193, 1901, and G. van Iterson. These Proceedings 

 24 April 1903. 



