22-1 KErOKT OF COMMISSIONER OF FISH AND FISHEKIES. 



bags, and so on, layer after layer, nntil 1 -") or -i) ])a,ii,s lia\"r Ix'cn piled 

 up. Heavy i^ressn re is then applied and continued 10 or 1l* liours, 

 when practically all tlie oil drains fi-oin the bags, leaving behind an 

 unctuous mass of the consistency of tallow or butter, composed of 

 nearly pure stearin, with a small quantity of debris and fillers. The 

 quantity of stearin removed depends on tlu^ tempiM-ature at wliich 

 the congealed oil is pressed. At the usual temperature of 28^ to 30° 

 F., a])Out 1:^ pounds are removed from each gallon of crude oil, the 

 latter weighing abt)ut 74 pounds. The stearin is sold at 5 or G cents 

 per pound and is used b}^ soap- and candle-makers and as a tallow 

 substitute in leather-dressing. 



Medicinal cod-liver oil should be exposed to the air as little as pos- 

 sible during the whole process of extraction, filtering, and pressing; 

 and as soon as the last operation is completed, it should be placed in 

 shii)i)ing packages and stored in a cool place until marketed. This 

 oil has a greenish tint, is almost tasteless and odorless. For the pur- 

 pose of making the oil lighter in color, it is sometimes bleached by 

 exjwsing it in a thin layer to the sun's rays for an hour or more. 

 Bleaching medicinal oil is an objectionable process, r(;sulting in no 

 particular benefit, and, on the contrary, is productive of much harm 

 when long continued. 



The style of the package in Avhich medicinal oil is placed is of much 

 importance. Since cod oil readily acquires the flavor of wood and 

 becomes disvjolored thereb^^ glass or metal receptacles are prefei-red. 

 Tin is much the best material when glass is not used. The Norwe- 

 gians use tin-lined bari-els. When wooden barrels are emjiloyed, 

 white oak is preferable to other varieties. 



J)ui-ing recent years nuiu}' manufacturing pharmacists have pre- 

 pared cod-liver oil in such a manner as to overcome the disagr(;eable 

 flavor and the even more objectionable gastric disturbance which so 

 frequently follows its use. These products are mostly in the form of 

 emulsions, gelatinous capsules, with sii-ups, creams, jellies, etc. 



Furthermore, some pharmacists rcunove the so-called "active prin- 

 ciples" in cod-liver oil, the oil itself being subsequently used for tech- 

 nical purposes. These "active principles" are extracted by means 

 of an alcoholic menstruum, then concentrated by evaporation and 

 dissolved in wine. They are j)laced on the market under various 

 proprietary names. In some factories the fresh livers, rather than the 

 oil, are used in manufacturing the "active pi-inciples," since the latter 

 are alleged to occur in far greater abundance in the liver tissues than 

 in th(^ oil. According to an account given by the proprietor of one of 

 these pi-cparations, the livers ai-e thoroughly' minced in a steam-power 

 ('hoi)[)ing-machin(^ and macerated for several days in large stirring 

 machines of special design, a menstruum being employed consisting 

 of diluted alcohol containing a small quantity of citric acid. The 

 extract is then drawn off and concentrated in vacuo at a temperature 

 of 40° F. When the li(juid is reduced to about the consistency of 



