13 



11.43 knwaiiune yielded 12.38 kuwainnn" ot'koji, or 100 parts l>y \\eii;lit nf tlic 

 rice gave 108.3 jiarts liy weight of knji. Tlie rice coi.t lined 14. 2% df water, and 

 the kqji contained 29.5%, therefore, deducting the water from each, we find that 

 85.8 parts of dry rice gave 76.4 parts of dry koji, equal to 89%, or in other words, 

 11% of material was lost by the dry rice. This loss is prnhally nearly all starch, 

 and if so, every 100 parts of rice converted into ki'iji would evolvt^ nearly IS parts 

 of carbonic acid. Now 107 lbs. of dry rice are converted into koji every day in 

 eacli chamber, and thus evolve 19.2 lbs. of carbonic acid ireisuiing 2240 litres. 

 The total capacity of each chamber cannot be more tlian 20000 litres, and there- 

 fore in order to remove the carlmnic acid formed a constant circulation nf air is 

 necessary. If this were not provided for the air would not only become irrespir- 

 able by the workmen, but would also become unfit for the growth of the plant 

 which requires a supply of o.xygen. At the same time care has to be taken that 

 the current of fresh air is not sufficiently rapid to lower the temperature of the air 

 within the chamber. The mode of ventilation depends upon the difl'erence in 

 temperature between the inner and the outer air, the inner air being warmer 

 rises up a square sliaft at the tVont end of the series of ]iassages. whilst the cold 

 air bringing fresh oxygen enters and flows along the floor of the chambers, until 

 in its tiu-n it is warmed and rises through the shaft to the air above. This 

 method is am])ly sufficient dm-ing winter when the difl'erence of temperature 

 between the air outside and inside is about 40' F, but when, as in the spring 

 and early summer the difference becomes less than iO^ F., frequent stojip.ages 

 occur. This, jierhaps, might be remedied by bmiiing a small lire at the foot of 

 the shaft, and thus artilicially causing a draiight, bnt as a smaller quantity of ki'iji 

 is required in sununer, it is not of so much importatice. 



In the germination of l)arley Day"' has shown that an anionnt of cisygen is 

 absorbed by tiie grain greater than is requirc^d to produce tlu; carbonic acid 

 liberated and he concludes that this increascil absorption of oxygen is not con- 

 nected with the liberation nf the carlmiiie acid. Whi'ther a similar absnriition 

 occurs in tiie present case is not known, but if, as is not improbalile, it does occur, 

 tlie amount of starchy material lost by the rice dming llie conversion into knji 

 will be even greater than that uiven almve'. Tiic aninnnl nf carbon oxiili/A'il 

 during the germination of the barley giain is said by 1 'ay l'> be abniit 2 5 per cent., 

 ami he linds that there is a pretty constant rclatinn between the carlion oxi li/.ed 

 and the wafer formed, which avi-rages 12 carbon to 18 2S water. Thus fur every 

 atom of carbon fixidized one molecule of water is lii)erated. a latio wiiicli would 

 agree with tiie (brmida for dex(ros(! (.'/• |||._,() , or in its siuqilesf Ibini ( I ll._, ( ). 

 Possibly a sinular relation may bi_- observed in tin- ease of koji ; that a large 

 lilieration of wijer does occur is evidenced liy the increase<l iK-rcentage contained 

 bv the koji fomp'ireil with tint in ihe rice, atid also li\- the moisture of tlie 

 atmosphere in fh(! chamber. II however, n lixeil relation were to exist it would 



Joiirnnl Ch-m. ?..<• Ifcso. Trai. ■ ,.. i',.-.ri 



