250 
Journal of Agricultural Research 
Vol. XXVII, No. 5 
The method is discussed in considerable detail by Magnus (30) and also 
by Fingerling {26, p. 291 , 292). 
Magnus, has reviewed and discussed in his text on the subject (30) all 
of the more important processes of straw hydrolysis which had been 
devised up to the date of its publication in 1919. In addition, he has 
given a detailed account of the theory of straw hydrolysis and of many 
of his own investigations. Though rather out of date now, it is the only 
text on the subject of which the writer is aware. 
In 1919 Jonscher (25) reported on his investigations in treating straw 
meal and wood meal with HC 1 and (or) NaOH, recommending some of 
the products as suitable for animal and human food. 
Within the past four years Honcamp and his coworkers have carried 
on quite extensive investigations into the relative merits of various 
methods of straw hydrolysis. In his first paper (27), published in 1919, 
he reports unfavorably on the methods proposed by Minck and Schwalbe 
for hydrolysis with hydrochloric acid. Such treatment makes the straw 
no more digestible. 
His second paper (22, p. 1-41), published in 1921, deals with hydrolysis 
of straw by calcium hydroxid without pressure. Such treatment in¬ 
creases the starch value above that of the original straw to about the same 
extent as does sodium hydroxid. Loss of organic substance is greater 
when the hydrolysis takes place under pressure than by simply boiling. 
In his third contribution (22, p. 42-63), published coincident with the 
second, he discusses the effect of hydrolyzing with sodium carbonate, 
which is similar to that of NaOH and Ca ( 0 H) 2 . Using concentrations 
of Na 2 C 0 8 similar to those of NaOH and Ca(OH) 2 employed, the fodder 
value of the straw was considerably improved. 
His fourth paper (25), published about the same time as the second 
and third, deals with hydrolysis by sodium hydroxid under pressure. 
Only cereal straw is suitable for such treatment. Results obtained with 
a definite amount of NaOH (3.5 kg. per 100 kg. of straw) were about 
the same as where twice that amount was used. 
In his most recent work (24) Honcamp investigated the Beckmann 
methods, using both sodium hydroxid and calcium hydroxid. His con¬ 
clusion was that the loss in crude and digestible nutrients was greater 
with NaOH than with Ca(OH) 2 . 
In addition to this series of five papers, he published a general paper 
(20) in 1919 with some rather important conclusions. He states that 
pressure cooking results in greater destruction of organic matter than 
when the cooking is done in open vessels, and that hydrolysis with NaOH 
results in a substantial increase in digestibility in rye, barley, and oat 
straw, but only slight increase in pea, seed beet, and rape straw. 
Semmler and Pringsheim (40) found that usually less than 50 per cent 
of the crude fiber of natural products is digested when the lignin content 
is in excess of 20 per cent, but up to 75 per cent may be digested in the 
case of straw hydrolyzed by sodium hydroxid, despite a much higher 
lignin content. 
Fingerling has made some important contributions to the subject. 
In addition to his numerous experiments already referred to (13, and 
26 , p. 289-292 ), he has investigated Beckmann's process quite thoroughly. 
In 1919 he published a paper (14) dealing with the influence of time of 
hydrolysis upon the amount of nutritive material liberated. The re¬ 
sults showed that the greatest amount of hydrolysis took place in the 
first three hours, and that action of the NaOH was practically completed 
