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difficulty to dispose of. I could see no difference, further than the flowers were 
fuller and more expanded. It is not improbable that the oil receptacles might 
have an abnormal development by manuring and particular care. I do not 
believe that it is a distinct variety. The yield of oil per acre from this kind 
is 8 lb. 
The yield of Chamomile flowers per acre is about 4 cwt. 
Pennyroyal yields about 12 lb. of oil per acre ; and so extremely variable is 
this plant in its yield of oil, that one grower informs me that he obtained only 
five ounces from a quarter of an acre ; of course he ceased to cultivate Penny¬ 
royal for distillation. 
The Provence Rose is extensively cultivated for the production of rose-water; 
large quantities are also dried for the London markets. The Damask Rose is 
cultivated by a few growers for drying, and is never distilled. 
During a favourable season 300 bushels of Roses are produced per acre. 
If all the Lavender and Peppermint cultivated were distilled, the amount 
of oil supplied by Mitcham will be about 21901b. 01. Menthse Pip., and about 
2060 lb. 01. Lavand.; but as a considerable quantity of Lavender is “bunched” 
and dried, the amount of oil supplied must be much less. 
Between 30,000 and 40,000 bushels of Roses are annually produced in 
Mitcham, and abolit eleven tons of Chamomile flowers. 
Great care is taken in gathering and drying these flowers. The Roses are 
collected before sunrise. 
They are dried in ovens heated by air, and are maintained at a constant 
temperature of 100° F. by a regulating arrangement. 
After the Chamomiles are dried they are “picked.” This operation consists 
in separating the darker flowers. 
The “bunched” plants are dried in open sheds, secluded from the action of 
direct sunlight. 
The stills are of very large capacity, holding from 1000 to 2000 gallons. A 
charge occupies from six to eight hours. The distillation is conducted at the 
lowest possible temperature; and, as soon as the contents of the retort have 
reached the boiling-point, the fire is withdrawn. 
The finest portion of the oil comes over during the first period of distillation, 
and the receiver is exchanged. Only two qualities of oil are generally collected 
and the receivers are exchanged after three hours’ run. 
There is a peculiar fragrance and delicacy in the oil first obtained, which is 
decidedly wanting in the product which comes over towards the end. 
I find that a much less proportion of camphor exists in the Mitcham oils 
than in oils generally. This might be due to their freshness, and to the 
peculiar alchemistical notions of the distiller of conducting everything in the 
dark. No doubt, exclusion from the actinic rays is as desirable for the preserva¬ 
tion of essential oils as other products of the vegetable kingdom. 
The oils generally are of very light specific gravity, and their refractive 
power is very great. 
In operating with such large quantities of water, involving as it must some 
considerable loss of oil, a plan was tried, some time ago, to economize this un¬ 
necessary consumption of the oil, by using the impregnated water for suc¬ 
cessive charges of the retort, but the expense of pumping and storing away this 
water was greater than the loss arising from the solution of the oil. 
The extracts obtained from Belladonna, Foxglove, Stramonium, Henbane, 
Poppies, and Elaterium, cultivated at Mitcham, ar t in their action and appear¬ 
ance very good. 
In the laboratory of Mr. William Hooper these cultivated plants have been 
very extensively consumed ; and there can be no doubt but that the uniformity 
of these extracts, as regards their medicinal activity, is due in part to cultivation; 
