518 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
[ December 17, 1891. 
diameter, measuring 67 cubic feet, and weighs 3 tons. Turpentine is 
obtained from the Silver Fir (Picea grandis), which bears heavy cones. 
Arbor Vitae wood made excellent posts and fences, lasting for fifty 
years. He dealt fully with the historical Cedar of Lebanon, Araucarias, 
Cupressus, Junipers, Larch, Wellingtonia, and Yews, &c. There was a 
good discussion, and several points of great interest were touched upon. 
A hearty vote of thanks to Mr. Cheal for his lecture was accorded. At 
the close of the mee'ing the members resolved to wind up the season by 
having a dinner, and they invited the horticultural and the Chrysanthe¬ 
mum societies to amalgamate with them for the purpose. 
ROYAL HORTICULTURAL SOCIETY. 
Scientific Committee. —December 8th. Present : Mr. Morris in 
the chair, Mr. McLachlan, Mr. Michael, Dr. Miiller, Rev. W. Wilks, 
Dr. Scott, Prof. Oliver, Rev. G. Henslow, Hon. Sec.; and M. H. de Vil- 
morin (visitor). 
Primula Forbesi, Franchet.—M. de Vilmorin exhibited growing 
plants and cut blooms of this new species. It was discovered by Abbh 
Delanay in the province of Yunan, China, growing wild in marshes and 
Rice fields, where it is practically an annual. The plants were raised 
from seed received from the Abbh, and under cultivation proves to be a 
most perpetual bloomer. It much resembles P. obconica in the suc¬ 
cession of flower stems, but otherwise is quite unlike it in appearance. 
The flower stems are very slender, and bear several (3-6) whorls of 
flowers, which, individually, resemble those of P. farinosa. It has 
produced but few seeds as yet, possibly requiring a high temperature. 
It does, however, well in a cool house. The specimens appear to be all 
of the long-styled form, which may possibly account for the paucity of 
seed. Thegrowing plants were presented by M. de Vilmorin to Kew, and 
to the Horticultural Society. A vote of thanks was given by the Com¬ 
mittee to M. Vilmorin for his interesting communication. 
Thelephora sp. (.?).—Dr, Muller exhibited what appeared to be some 
species of this genus growing round the stems of Rhododendrons in 
peaty sand. He thought it appeared to be parasitic. It was forwarded 
to Kew for further examination and report. 
Fog and Rain. —Prof. Oliver asked M. de Vilmorin if he had ex¬ 
perienced in Paris any ill effects of fog comparable to those familiar to 
growers in the neighbourhood of London. He replied in the negative, 
as a typical yellow fog is unknown in Paris. He observed that was 
sometimes a well-marked local increase of rain induced to fall, through 
condensation brought about by trees. 
Narcissus bulbs attached by Merodon. —Mr. G. Lee of Clevedon, 
sent bulbs with this well-known pest. The only methods of destruction 
are either to cut out the portions containing the grubs ; soaking the 
bulbs in water to drown them; or else by destroying the bulbs 
altogether. 
Bentliamia fragifera, fruit. —Mr. R. G. Lakes of St. Austell, Corn¬ 
wall, sent some fine ripe specimens of the fruit of this tree. 
Citrons. —Mr. P. Crowley, F.L.S., forwarded two fine fruits of 
Citrus medica, grown at Waddon House, Croydon. 
j ' ' ) n : 
EXPERIMENTS WITH POTATOES. 
Mr H. Chancellor of Chessington Hall, Surrey, occupies a recog¬ 
nised position as a scientific and practical cultivator of Potatoes and 
other crops. He derives much pleasure in conducting experiments, and 
the information he has thus gained has no doubt be n turned to 
profitable account. His early training at the Agricultural College, 
Cirencester, where he was a successful student and prize essayist, im¬ 
pressed him with the importance of great exactitude in his various 
trials, and of these he keeps careful record. This year he tried the 
Bordeaux mixture as a disease preventive and found it beneficial; he 
also tried tubers of different sizes for planting, as well as the effects 
of artificial manures, and has favoured with the following report of 
some of his experiments during the present year :— 
“ The past season has proved to be quite exceptional and particularly 
unfavourable for testing experimentally the value of any special plan of 
cultivating the Potato crop. This applies in a marked manner to the 
application of different artificial manures, and in trying to ascertain the 
relative advantages from the use of minerals and nitrogenous manures 
together and separately I have been met with not a few of those con¬ 
tradictory results which are very generally found in any series of experi¬ 
mental plots. The heavy gales and rains which prevailed during the 
latter half of August caught the main crop of Potatoes in full vigour of 
growth. As the outcome of such violent commotion among the haulm, 
accompanied by a very low temperature and excess of moisture, the 
hitherto luxuriant foliage quickly merged into a mere forest of naked 
stems. This was very generally the case, the gales extending through¬ 
out the length and breadth of the country, and though the tubers 
continued to swell somewhat while the haulm kept green, still the 
Potato plants were unable to derive much further benefit from the 
artificial dressings lying at their feet. In venturing to give you a state¬ 
ment of returns from some of my experimental series, I would remark 
that I scarcely remember a season in which I have noticed so little 
proportionate gain in produce from the use of artificial manures. It 
might reasonably be expected that highly forced vegetation would 
suffer from such a sudden visitation of ungenial weather in this critical 
stage of growth more than that growing under normal conditions. So, 
in all plots heavily treated with nitrate of soda or sulphate of ammonia, 
the returns are no. at all commensurate with the increased outlay. 
Influence of Sets. 
Variety , Beauty of Hebron (early'), all Whole Sets. 
YIELD. 
Ore :od, p’antei with 80 sets, averaging 1 oz. 
it n it it i! 2 oz. 
115 lbs. 
122 
The Bruce (late). 
One rod planted with 72 sets, averaging 
i) >i » j> » 
)i >> « n » 
» » » » » 
h OZ. 
1 OZ. 
14 OZ. 
2 oz. 
112 
135 
142 
146 
ft 
n 
a 
>> 
“ The larger sized sets showing uniformly a better yield than the 
small. The shortness, of the period of growth this season was against 
the smaller sets, the plants starting somewhat weaker. Some few rods 
were lifted, planted with small baker’s chats (ninety sets per rod) and 
weighed against others planted with ordinary full seed size (seventy-two 
sets per rod), and in all cases the weight per rod was the same, and the 
proportion of ware to middings in the produce agreed. 
Influence of Soil. 
Soil Sandy Loam. 
Yield. 
Beauty of Hebron (early) 20 sets (2 lbs.) . . 44 lbs. 
Soil Heavy Loam. 
Yield. 
. 36 lbs. 
Jeannie Deans (early) 
ft 
„ ... 53 „ 
... ... 
44 „ 
Magnums 
ft 
49 
,, ... ,, 
. 
41 „ 
The Bruce 
ft 
„ ... 51 „ 
... ... 
41 
Reading Giant 
ft 
„ ... 52 „ 
• •• 
47 „ 
Her Majesty 
tf 
„ ... 53 „ 
. 
41 „ 
The Major 
ft 
„ 50 „ 
. 
38 „ 
“ The Potatoes were planted rather earlier on the 
light soil, 
and the 
weather favoured thi3 description of land. 
Influence of Manures. 
Mineral Superphosphate and Basic Slag (Phospihate Powder) Rate 
per Acre. 
Mineral superphosphate, 5 cwt 
Basic slag, 5 „ 
Mineral superphosphate 5 
and nitrate of soda, 1^ „ 
Basic slag 5 „ 
and nitrate of soda, 1| „ 
Nitrate only, 1J „ 
No artificial, 
PRODUCED. 
1 rod (80 sets) ... 
... 112 lbs 
ft 5» 
... 128 „ 
ft if 
| ft it •••. 
... 140 „ 
... 128 „ 
if ft •** 
... 116 „ 
... 106 „ 
“ Basic slag shows single-handed a gain over superphosphate, but when 
nitrate of soda is added the positions are reversed, and the basic slag 
shows better results than nitrate of soda. 
In another series gypsum showed a good return, but salt was 
uniformly unsatisfactory, as might be expected this wet season. Sulphate 
of potash alone very unsatisfactory, but with nitrate of soda better. 
Sulphate of magnesia well repaid outlay (slight cost). Basic slag alone 
generally gave better return than mineral superphosphate. Bonemeal 
about equal to basic slag. 
Nitrate of Soda v. Sulphate of Ammonia. 
rate per Acre. 
Two rods lifoed, nitrate of soda, ... 1^ cwt. 
m a n n ••• » . 
,, ,, sulphate of ammonia, 1^ „ . 
» » >) i) ^ „ . 
YIELD. 
283 lbs. 
251 ,, 
276 „ 
241 „ 
“ Soil, very stiff clay, variety Magnums.—The heavier dose of both 
salts showing a less yield of tubers. The foliage on the 3 cwt. plots was 
over-luxuriant, and suffered from heavy gales and rains. A longer and 
drier season and the heavy dressings would probably have given the 
higher returns. 
Nitrate of Soda v. Sulphate of Ammonia with Minerals. 
RATE PER ACRE, 
One rod, 70 sets, 2 basic slag 
2 superphosphate 
1 sulphate potash 
2 nitrate of soda 
One rod, 70 sets, 2 basic slag 
2 superphosphate 
1 sulphate potash 
2 sulphate of ammonia 
Titrate of Soda, Sulphate of Ammonia, and Soot. 
2 cwt. nitrate of soda, 70 sets (giants), produced . 150 
2 cwt. sulphate of ammonia, 70 sets (giants), produced ... 130 
40 bushels of soot (sown in drills when planted) . 146 
YIELD. 
. 148 lbs. 
. 139 lbs. 
“ It will be seen that nitrate of soda has given a better return than 
sulphate of ammonia throughout this last series. The great difference 
jn value between these soluble salts is also a consideration. Many of 
0 ur leading growers of Potatoes maintain that sulphate of ammonia is 
