Pure and Mixed Linseed-Cakes, 
29 
Indigo-sccd-cakc, it appears from the preceding- analysis, is 
very poor in oil, nor does it contain a liigli percentage of albu- 
minous compounds. Apart from its disagreeable taste, whicli 
in a great measure spoils the fine flavour of linseed-cake, with 
which it is occasionally mixed, it does not possess a high feeding 
Aalue. 
This cake was sent to me for examination by an oil-crusher, 
and but for this circumstance I probably should not have beea 
able to detect Indigo-seed in a sample of linseed-cake, which 
was sent to me for examination soon after I reported that the 
indigo seed-cake was not poisonous, but a poor and disagreeable 
tasting cake. Notwithstanding the unfavourable report I had 
given, indigo seed-cake appears to have found its way into 
linseed-cake mills. 
18. SiJ'tirif/s, or Screcninris-Cake. — Dirty linseed, as already 
fully described in the preceding pages, contains a host of small 
weed-seeds, dirt, and similar impurities. In mills in which pure 
linseed-cake is made, these impurities are removed from linseed 
by screening or sifting. The siftings or screenings, however, 
are not thrown aside, for they possess a commercial value of 
their own, and fetch a much higher price than they are worth 
intrinsically, inasmuch as they are either employed for mixing 
with fairly clean samples of linseed, and producing 2nd and 3rd 
([uality samples of " genuine linseed as imported," or are pressed 
into cake. 
A sample of siftings-cake, on analysis in my laboratory, 
yielded the following results : — 
Composition of Siftings, or Screenings-Cake. 
Moisture 10 "57 
Oil 6-45 
* Albuminous compounds (flesh-forming matter) .. 18 "44 
Starch, mucilage, and digestible fibre 35 '94 
Woody fibre (cellulose) ]4'13 
f Mineral matter (ash) 14 '47 
100-00 
* Containing nitrogen 2*95 
t Containing sand 7 '37 
Siftings-cake, as shown by the preceding analytical result, 
contains much sand, and is one of the most abominable com- 
pounds that can be incorporated with feeding stuffs. It appears 
to be a regular article of commerce : and, although it contains 
hardly any linseed, and generally is full of wild mustard, and 
for that reason decidedly injurious to cattle, it is occasionally 
sold at a low price as linseed- cake. 
Not long ago a farmer sent me a so-called linseed-cake, which 
