in the watei' above the yeast but little carbon dioxide is dissolved 

 In the following caloulation the water has been supposed to contain 

 no carbonic acid, so a small, practically to be neglected, mistake is made. 

 This mistake is completely to be avoided by refreshing the water above 

 the sunken yeast, which too sliould be taken away with a dropping 

 syringe. The sunken yeast is divided in the remaining water and 

 brought into the saccharimeter with a capillary tube. 



§ 3. Method of using. 



In the tirst place the microsaccharimeter is to be tilled with a 

 certain quantity of dried, cleaned mercury. 



The nut-wing is unscrewed and the glass appai-atus placed as 

 tig. 2 shows. The tilling is done by the funnel, with a dropping 

 syringe. When the funnel is full, it is carefully raised ; the mercury 

 streams to the reservoir A and remains partly in the capillary tube. 

 The next lowei'ing of the funnel makes the mercui'y stream partly- 

 back. By addition or i-emoval of mercury the quantity' can be 

 taken so, that the reservoir with its neck and the capillary tube is 

 filled as far as or just past the zero-point. To control this, the funnel is 

 raised till the mercury reaches the border of the opening of the 

 neck ; tlie mercury will then be adjusted at zero, or between the 

 tirst marks. After the apparatus has been tilled with mercury, it 

 is placed in the original position and with the aid of a metal spatula 

 a bit of paraffin, melted on that si)atula, is spread on the polished 

 surface of the neck. 



Only a thin cover is wanted, but it should reach the border of 

 the opening; it is even to be preferred to cover the inner-wall of this 

 neck over a short distance, but it is not necessary. 



Now the nut-wing is fastened, but so, that the glass apparatus 

 can still be moved in the cork and remains in every required posi- 

 tion, when released. Then the apparatus is placed so that the 

 tangentplane lo the mercury level in the neck coincides with the 

 paraffin cover. Therefore the eye is kept in the tangent-plane to 

 this surface and the funnel is to be raised till the mercury meniscus 

 can just be seen. In this phase the fii\it rending of the mercury 

 in the calibrated tube is made. 



By the action of the capillarity in that calibrated tube a strongly 

 convex meniscus is formed and (he position of the utmost tangent- 

 plane is to be read without difficulty with the naked eye up to in 

 tenth parts of the calibration. 



Next a drop of the fernienting licpiid is brought on Ihe mercury 



