PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 453 



ducod into the converter; also with safety valves, steam gauge, water 

 gauge, thermometer, pipe for escape of steam, exit cock at bottom, and a 

 worm or distilling pipe, through which the high pressure steam is allowed 

 to blow off out of the converter, carrying with it the essential oil and em- 

 pyreiimatic fatty matters vaporized ai^d gasified by the action of the high 

 temperature to whicli the mixture is submitted. 



In carrying out the process of converting starch or fecula into glucose 

 sugar, according to this invention, it is preferable to employ the starch 

 or fecula, sulphuric acid and carbonate of lime in the following proportions: 

 2,240 lbs. (one ton) of starch or fecula; 1,120 gallons of water, being five 

 times the weight of starch or fecula; 112 lbs. of sulphuric acid, being five 

 per cent, of the weight of the starch; 168 lbs. of purified carbonate of lime, 

 being 7i per cent, of the weight of the starch. 



The manner in which the process is conducted is as follows: Place in 

 the converter above described 56 lbs, of sulphuric acid of 156 deg. density, 

 diluted with 560 gallons of water- the mixture is then to be heated up to 

 212 deg, Fah. During the heating of the acidulated water in the converter, 

 place into an open wood vessel, which ma}' be called a diluting vat, pro- 

 vided with steam pipe, let-out cock, and with stirring apparatus, the other 

 660 gallons of water, in which is aiso to be diluted the other 56 lbs. of sul- 

 phuric acid, which acidulated water is also heated up to S5 deg. Fah.; as 

 8oon as this temperature of 85 deg. Fah. is attained, gradually pour into 

 the said diluting vat the 2,240 lbs. (one ton) of starch or fecula, stirring 

 the mixture well, and raise the temperature to 100 deg. Fah., the stirring 

 maintHined the whole time. Then gradually pour the diluted starch heated 

 at 100 deg. into the converter, in which the acidulated water is kept boil- 

 ing, continuing to blow in steam in order to keep the temperature in the 

 mixture throughout this part of the process to its original heat of 212 deg. 

 Fah. 



Wiien the whole of the diluted starch is introduced into the converter 

 shut off the cock of tlie pipe through which the diluted starch has been 

 conveyed into the converter, and then continue to blow in steam so as to 

 raise the temperature in the mixture up to 320 deg. Fahrenheit, equivalent 

 to a pressure of six atmospheres,, or 90 lbs. per square inch. When this 

 temperature of 320 deg. Faiirenheit is attained, open the cock of the worm 

 or distilling pipe through which the steam escapes, carrying away out of 

 the converter the essential and empyrcumatic fatty matters which vaporize 

 and gasify at about 270 deg. Fahrenheit; hence by heating and maintain- 

 ing the temperature in the mixture to the higher degree of 320 deg. Fah- 

 renheit, not only are the said vaporized and gasified essential oil and empy- 

 rcumatic fatty matters readily distilled off, separated and got rid of, but also 

 the whole of the gum converted into glucose sugar is obtained, which con- 

 version takes place at th(^eraperature of about 2T5 deg. Fahrenheit. Con- 

 tinue to heat and maintain the temperature of 320 deg. Fahrenheit in the 

 mixture, until by testing with iodine all the starch is found to be converted, 

 and further, until by testing with silicate of potash or acetate of lead, it 

 is found that there is no dextrine or gum in the saccharified liquid. For 

 the purpose of testing proceed as follows: Draw off out of the converter 

 a sample of the mixture, then neutralize the sulphuric acid, pass it through 



