and in the Stack in Haymaking. 39 



Detailed Composition. 



J)ried at 212° Fahr. 



Moisture 18-33 



Fatty matters 1-70 .... 2-08 



*Soluble albuminous compounds .. .. 1*94 .... 2"37 



Mucilage, gum, brown extractive matters) q.^. ii-qi 



and traces of sugar \ "^ ' ' " 



Acetic acid 1-93 .... 2-36 



Digestible fibre 23-01 .... 28-19 



flnsoluble albuminous compounds .. .. 8'75 .... 10*71 



Indigestible woody-fibre (cellulose) .. .. 28-53 .... 34-93 



Soluble mineral substances 3-98 .... 4-87 



Insoluble mineral substances 2-59 .... 3-18 



100-00 100-00 



* Containing nitrogen -31 .... -38 



t Containing nitrogen 1-40 .... 1-71 



The occurrence of a considerable amount of acetic acid in this 

 hav, and the all but complete absence of sugar, deserve a special 

 notice. Vinegar-manufacturers are well acquainted with the fact 

 that all sugary substances may be employed for the production of 

 vinegar, and that in the so-called rapid vinegar process a dilute 

 alcoholic liquid in the presence of a porous substance, such as 

 wood-shavings or chopped straw, or under the influence of a 

 ferment, is rapidly transformed into vinegar. Scientific chemists, 

 moreover, have pointed out the relation which exists on the one 

 hand between sugar and alcohol, and on the other between alcohol 

 and acetic acid — the acid of vinegar — showing that the latter 

 is formed by absorption of oxygen, in other words that acetic 

 acid results from the oxidation of dilute alcohol. It is clear, 

 therefore, that the acetic acid found in the heavier hay was pro- 

 duced at the expense of the sugar present in unfermented or only 

 slightly fermented hay. 



Subsequently I had an opportunity of examining a rick of 

 clover-hay, which became so hot in the interior that it had to be 

 disturbed. It had been made in a bad season, and was stacked 

 when too moist. On removing the top-layers of the rick the 

 vapours emanating from the heated hay were found to have 

 a peculiar pungent irritating odour, which particularly affected 

 the eyes. A chemist could not doubt for a moment that these 

 irritating vapours were due to the volatile inflammable com- 

 pound which has received the name of Aldehyd. The same 

 pungent odour may be noticed in vinegar manufactories at a 

 certain stage of the vinegar process, and it is well known that 

 aldehyd is produced in abundance when weak alcoholic liquids 

 are allowed to trickle slowly over wood-shavings kept loosely in 

 perforated capacious vats freely admitting air. In this operation 



