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SELECTED ARTICLES. 
Mugwort, 1 : 2. Product by vapour the best. 
Elecampane, (dried root) 1 : 4. The product by both 
modes contained helenine which separated on standing; the 
product by the naked fire gave the largest product, as well as 
the most odorous. The difference, however, was slight. 
Blue bottle, 1:1. Product by vapour was limpid, that 
by the naked fire contained white flakes, and had rather the 
most taste. 
Borage, 1 : L After a lapse of three months, the product 
by naked fire was spoiled, and I could not make a comparison. 
Holy thistle, 1:1. A small quantity of a concrete, white, 
volatile oil was separated by each process. There did not ap- 
pear any difference in the products, though that by steam 
kept the best. 
Scurvy grass, 1:2. The first product by naked fire was 
equal in weight to the plant; was milky and very sapid; the 
same with the second; the third had less taste, and the fourth 
scarcely any. By steam it was transparent throughout, and 
the third product had very little taste. I repeated this expe- 
riment several times, and always obtained a better product by 
the naked fire. Besides the acrid oil that pre-exists in the 
first plant, can there be a production of an additional quantity 
by action of cold water; the formation of which is prevented 
by the action of steam? 
Cress, 1 : 2. The same as above except that the product 
is not so strong. 
Fennel, 1:2. I obtained the best product from the dried 
plant, but I am doubtful of this result, as I only made the ex- 
periment once. 
Fennel, (dry seeds) 1 : 4. The fourth product by both 
operations was still charged with oil; the product by steam 
was the best, but at the same time, it was not as agreeable as 
that made from the leaves. 
Juniper, 1:2. I obtained the most essential oil by steam; 
but the odour of both products was so powerful that it was 
impossible to ascertain which was the best. 
Hyssop, 1:2.1 could not appreciate the difference between 
