572 
THP TROPICAL AGRICULTURIST. 
[February 2, 1891. 
before the diggings began each was capped by a 
hillock, or “ kopje,” They are 17 in number, and 
run in a straight line for about 120 miles. 
The question of their origin has recently been dis- 
cussed by M. Dambree, a well-known French geologist, 
at a meeting of the Acad6mie des Sciences, Paris. 
They have, of course, been opened by an eruptive 
force from the interior of the earth’s crust, but they 
differ from the usual volcanic cracks or fissures. M. 
Dambrde attributes them to the outburst of imprisoned 
gases, and has made a number of experiments at the 
Laboratoire Centrale des Poudres et Salpetres, in 
Paris, to prove his theory. Explosions of dynamite and 
gun-cotton were made iu a steel cylinder or mortar, and 
the escaping gases made to perforate masses of rock. 
Limestone, gypsum, slate, granite, porcelain, glass, 
crystal, and steel were all fractured and bored in this 
manner. It follows from his experiments that gases 
at a high velocity, say exceeding 1,300 metres a second, 
and especially when aided by heat, are powerful agents 
of geological erosion. They are able to bore regular 
vents or chimneys in rocks, if there is a crack or fissure 
to concentrate their energy in one spot. The diamond 
vents of South Africa are, in bis view, the effect of 
compressed gases exploding from the interior of the 
earth at certain points along a line of fissure ; and the 
strise or grooves observed on the sides of the vent are 
another proof of this explanation. 
Professor Liversidgo, F. R. S., of the University of 
Sydney, has found that certain fungoid growths have 
the power of removing gold from water containing 
it in suspension or in solution. Bottles of distilled 
water containing finely divid< d gold which had been 
reduced from a weak solution of the chlori 'e by 
phosphorus dissolved in ether were allowed to stand 
for some years, and it was observed that while some 
of them cleared, others retained the ruby or purple 
colour characteristic of gold thus reduced. Examination 
showed that the clear bott'es had a pnrpL-blue growth 
in them, which, under a microscope, appeared as a mass 
of matted filaments. When dried over a spirit lamp, 
these filaments exchanged their purple tinge for the 
metallic lustre and colour of[goId. A simi'ar change took 
place when the growth was rubb’din a mortar. 
In some cases the mould or fungns was white and 
blue-black. The white growths had a blueblack nucleus, 
and floated on the water. They had an oval shape, 
and were about |in. in length. Ether or alcohol is 
food for such growths, and pho.sphotus is favourable 
to their growth. There was little or no fu ^goid when 
other Bolventswere used for the phosphorus ; for instance 
carbon bisulphide, chlor iform, or turpentine. 
Professor Livereidge finds that the mould from 
cheese or banana skins, as we'l as bread and other 
organic bodies, will, when placed in water containing 
gold, either in suspension or soluiion, remrva it, they 
acquiring, at the same time,thecharacteri.stie blue colour. 
A French chemist, M. Aim6 Girard, ha.s show'n that 
the potato called “ Richter imperator ” is well-fitted 
for the production of alcohol by distillation on a com- 
mercial scale. At one operation 78,000 kilogrammes 
of potatoes were treated, and 10 litres of alcohol, 
absolutely pure, were obtained Irom every 100 kilo- 
grammes of the tuber. Another distillation gave 14 
litres for the Isame quantity of roots. The “dmff” 
which resulted was readily eaten by cattle. — Qlohe. 

The Champion Swede Crop. — Lord Wantage has 
this year grown on his Home Farm at Ardington, 
Berks, an enormous crop of Sutton’s Champion 
and Sutton’s Crimson King Swedes, weighing 
just upon 40 tons per acre. The individual 
roots were of excellent shape and quality ,and 
were awarded the Champion Prize given by Messrs. 
Proctor and llylaniis, competed for by farmers in the 
counties of Hereford, Silop, Stafford, Warwick, 
Worcester, Gloucester, Berks, Hants, Surrey, Oxford, 
Bucks, Herts, Bedford, Northampton and Huntingdon. 
Some of these roots will he exhibited on Messrs Sutton 
& Hons’ Stand at tlio Smithfield Club Cattle Show 
next mouth, and will bo well worthy a visit. 
Pine-Apple Fibre.— From Mr. E. W. Dana, Lake- 
wood, N. J., U.S.A., referring to an article on Pine- 
Apple fibre which was published in the Society’s 
Journal and reproduced in the Scientific American, 
and asking if the writer could furnish him with further 
particulars as he is greatly interested in the subject. 
A small sample of the fibre was sent to Mr. Dana, 
and he was informed that there is early prospect 
of the Mauritius aloe fibre machine being tried on 
pine-apple leaf in India, when the results will be 
published in the Proceedings. — Agricultural and Horti- 
cultural Society of India. 
Our Wealth of Live Stock. — Some interesting 
calculations of the value of the live stock held by British 
and Irish farmers, prepared by Mr. R. E. Turnbull, are 
published in the Journal of the Newcastle Farmers’ 
Club. They are evidently founded, as far as the unmber 
of animals is concerned, upon the official statistics col- 
lected in Juno of each year. The following table shows 
the estimated value of the live stock in 1887 and 1889, 
and the increase in each case within the two years ; — 
Value of Farmers’ Live Stock in the United Kingdom. 
Increase in 
Description of Total value Total value total value 
Live Stock. in 1887. in 1889. per cent. 
Cattle £100,018,452 £120,702,141 207 
Sheep 38,417,735 50,826,3.57 323 
Piis 6.511,675 6,835.263 5'0 
Horses 35,778,875 45,807,720 28’0 
Mr. Turnbull concludes that the total value of the live 
stock of this country, including poultry and goats, was 
last year £227,771.481, or at the rate of £4 15s per 
acre, whilst in 1887 it was only £183,806,737, or £3 
16s 9d per acre. The increase within the two years 
has thus been £43,694,744 or I8s 3d per acre. — Bell’s 
Wee'-ly Mesenger. 
Production of Gdtta Peecha.— The probabilities 
of a future scarcity of gutta percha has been a subject 
of concf-rn to the French government, which accord- 
ingly sent a scientist (M. Serullas) to the Malay 
peninsula and the adjacent islands to investigate and 
report on the matter. The results of some of his 
labors have recently been made public. M. Serulla.s 
states that until some substitute is discovered gutta 
percha is absolutely indispensible to submarine tele- 
graphy, for other gums cannot be used for the purpose 
wi‘h any practical results, as they«.do not possess 
the proper qualities. While good isonandra trees (from 
which this gum is taken) are to be found only in the 
Malaysian Archipelago and the Malaca peninsula, bad 
species grow all along the equatorial lands- Many 
efiorts have been made to use the gutta percha 
produced from the inferior trees, but they have all 
failed. It has been found that submarine cables laid in 
the same waters lasted same according to the quality 
of the gutta percha uesd in the covering. The cause 
of the scarcity of genuine gutta percha is explained 
by M. Serullas by the fact that the Malaysian 
natives began by cutting all the trees as soon as they 
found them in a producing condition. Then, after 
having thus prevented the production and mul- 
tiplication of the species, they attacked the youngest 
trees. Liter on they felled trees giving an inferior 
gutta percha snd mixed the gums, which were 
sold to Chinese merchants, who adulterated and 
weakened them still more. The extent of that blind 
destruction is sliown by the following figures. In 
1845 only 9.000 kilograms (the kilogram is equal to 
21/5 pounds) of gutta percha were exported to Europe ; 
in 1857 240,000 kilograms were exported. In 1879 
the amouut sent from Sumatra reached 135,000 kilo- 
grams, and from Borneo 1,300,000 kilograms. It 
was calculated that in order to obtain that amouut 
the natives must have cut more than 5,000,000 trees. 
In view of this situation France, England and Holland 
in 1881 sent scientific missions abroad to study the 
question, and to explore the producing regions of 
Malacca and Malay Islands. It was discovered that 
it was next to impossible to find adult trees, and 
that the situation was nearly desperate. England 
caused bills to be posted prohibiting the cutting of 
gutta purcha trees, and Holland ordered plantations 
of thorn to be made, hut the latter only produced 
pccies of inferior quality,— .5 raefcireefs. 
