44^ 
BLOOD ALBUMEN. 
At the last meeting of the German Polytechnic Association held in 
New York, a late patent for the manufacture of albumen and prussiate 
of potash from blood, issued by A. H. Hirsch, in Chicago, was dis- 
cussed. The old manner, still employed in Europe for this purpose, was 
described in detail, and amongst the disadvantages of the same it was 
mentioned that it consumed too much manual labour to be practicable 
in this country (America), as well as too much time, causing in the 
manufacture during warm weather the emission of unpleasant and 
unhealthy odours, which are the more objectionable here, as large 
quantities of blood can only be obtained in our larger very populated 
cities, especially the two great cities of the West, Chicago and 
Cincinnati, where the continual complainers about the " slaughter-house 
nuisance " loudly protested against any manipulation which would keep 
quantities of blood for several days in or near the city at a temperature 
most favourable for putrefaction. 
In Chicago experience had shown that a wind blowing northward 
carried the most disagreeable perfume imaginable from certain glue- 
factories, situated about six miles south of the city, to the latter, per- 
vading not only every street and alley all over its vast extent, but 
filling every house from basement to garret with the most abominable 
odour, sparing neither the marble palace on Michigan avenue nor the 
humble cottage in the distant prairie on the outskirts of the Garden 
City. The terrible scourge of the small-pox, which made such havoc 
in Chicago two years ago, and also made its appearance amongst the 
terror-stricken inhabitants last year, was chiefly attributed to this 
pestilence in the air, assisted by drinking water polluted with the de- 
caying offal of the factories mentioned. 
The old European, primitive method of manufacturing albumen has 
the other disadvantage of producing but a small yield of good albumen 
from the blood, the greater part being of a dark colour, making 
it unfit for calico-printing, the main channel for the consumption of 
albumen. 
This was very apparent even to the superficial observer of the old 
method, which consisted mainly in receiving the fresh blood in shallow 
dishes, exposing the same to rest, and pouring the clear serum off from 
the fibrine settled at the bottom of those basins. Even in case of per- 
fect separation this pouring- off can never be done completely enough 
to prevent the retention of a considerable amount of serum by the 
blood-corpuscles, or an admixture of the latter to the serum. Con- 
sidering the old method of employing blood for the production of 
prussiate of potash, it had always been thought a disadvantage that this 
material was bulky, being, in the liquid state, not handled with such 
facility as other animal offals and sources of nitrogen. 
vol. vi. 3 A 
