COLLECTIONS AND RECOLLECTIONS. 
489 
ARTICLE XI.—COLLECTIONS AND RECOLLECTIONS. 
Diseases of Melons, and their prevention Noticed.— 
Many gardeners experience much difficulty from the effects of Red 
Spider and Canker in Melons, the former being caused by keeping 
them too dry, and the latter arising from too much moisture. In or¬ 
der to avoid these evils, the following directions should be particularly 
attended to:—When the weather is hot, or there is a strong heat, it 
is necessary to be free in the application of water, especially round 
the sides of the boxes; for when the plants cover the bed, it will not 
be requisite to give any in the centre over the stems. When the 
plants cover the bed, always water without a rose, observing that it 
should invariably be done early in the morning, and when the wea¬ 
ther is fine, so as to allow the vines to get dry before night, which 
would not be the case, if watered in the afternoon; and should the 
weather prove dull the next day or two or three days, they are sure 
to become cankered. The only mode of cure for the canker is to 
keep the plants dry, and give a good heat; being careful at the same 
time not to run into the other extreme, by assisting the generation of 
Red Spider. But if the plants are kept thin of Vine, and water be 
applied in the manner before directed, no fear need be entertained of 
either of the disorders. Thos. Hallum. 
Diamonds.— A striking proof of the extraordiary differences of 
appearances which the same body may assume, and also of the in¬ 
trinsic worthlessness of some of those objects on which Society sets 
the highest value, occurs in the instance of charcoal: Every one 
knows the enormous price at which diamonds of good quality and 
size are estimated. " The celebrated Regent diamond, which was set 
in the handle of the late emperor Napoleon’s sword of state, is now 
valued at £260,000, although it weighs only about If ounce, and 
was originally purchased for £20,400, by Thomas Pitt, Grandfather 
to the great Earl of Chatham, while governor of Madras. Yet this 
precious ornament is neither more nor less than a piece of charcoal ; 
and, surprising as it may appear to those hitherto unacquainted with 
the fact, it is well proved, by numerous experiments, that between 
the diamond and charcoal, there is almost no difference of composi¬ 
tion : the diamond burns in oxygen with brilliant flame, and, like 
charcoal, forms carbonic acid : like charcoal, it forms steel by com¬ 
bination with iron : and the difference between the two bodies seems 
to be chiefly in their state of aggregation, the diamond being harder 
and crystallised. It is also a little purer in composition. The pure 
portion of charcoal is distinguished among chemists by the name of 
Carbon .— Lard. Cat. Cyclop. — Chemistry. 
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