f eptemter 22, 1892. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
253 
W E have received a carefully prepared and, we believe, 
thoroughly accurate record of experiments in the prevention 
of the Potato disease, which can scarcely fail to be of wide interest, 
and our readers can draw their own deductions from the facts 
set forth. As will be seen, the varieties of Potatoes are those 
in general cultivation, and are not restricted to Messrs. Carter’s 
specialities. They embrace early, midseason, and late sorts, the 
object in view being to have a trial as fair as a trial could be, 
conducted entirely by Mr. H. F. Moore, Editor of the “ Mark 
Lane Express” and “Bell’s Weekly Messenger.” Mr. Moore, 
having had experience in France in combating the Potato disease, 
determined to follow with precision the practice of his friend 
M. Aime Girard. Though a drenching rain occurred three days 
after the dressing was applied it did not wash off the mixture, as 
it was apparent enough when we examined the plots ten days 
subsequently. At that time there was no disease, and the dressing 
appeared to have appreciably arrested the growth of the plants, 
therefore the non-dressed plots looked rather the better of the 
two. 
It began to be feared that labour and material had been 
wasted, but the heavy rain on August 27th and 28th was followed 
by a decided outbreak of the murrain. The tops on the undressed 
plots speedily collapsed, while on the dressed plots they continued 
growing. This prolonged growth had the happy result of both 
increasing the total yield of the produce and diminishing the extent 
of the disease. This is clearly shown by the figure on page 263, 
and the difference was even more striking when the crops were 
examined on the ground. On the undressed plots they were in 
large unsightly heaps ; on the dressed plots, a mere handful 
in comparison, or to be exact, 11 lbs. against 6 cwt. 3 qrs. 11 lbs. 
The total gain in sound produce is at the rate of nearly or quite 
2 tons per acre, the actual gain on less than half an acre being 
18 cwt. 19 qrs. 18 lbs. The cost of the dressing, including material 
and labour, was at the rate of £1 an acre, therefore the investment 
proved decidedly profitable. 
Record of Experiments. 
For six years past the French Government have been making 
experiments, under the direction of Dr. Aime Girard, in order to 
test the value of the Bouillie Bordelaise as a preventive of the 
dreaded Potato disease (Pbytophthora infestans), and in the early 
part of last year that distinguished chemist was able to report that 
the results year after year had been so satisfactory that the mixture 
might with confidence be recommended as a preventive of the 
disease. Since then a number of experiments have been made 
not only in other countries of Continental Europe, but also in the 
United Kingdom, with varied results, and this year Messrs. 
James Carter & Co., the well-known seed firm, of 237 and 238, 
High Holborn, London, W.C., decided to devote an acre of land on 
one of their seed farms at Bromley, in Kent, to an experiment, and 
further, that it should be conducted on identically the same lines as 
those on the French Government Farm at Joinville-le-Pont. The 
direction was put in the hands of Mr. Henry F. Moore, the well- 
known agricultural writer, who consulted M. Girard, in order that 
the chemicals used might be of the same strength and quality as 
those used in France. 
The experiment was made on a field of a little less than an 
acre of Potatoes, which were planted in ten long double rows on 
April 8th, the drills being 36 inches apart, a distance which Messrs. 
Carter believe will be found more remunerative than if planted 
more thickly, as it permits the rays of the sun to penetrate the bed, 
No. 639 .—Yol. XXV., Third Series. 
an important factor in the development of this crop. The varieties 
plan‘ed were as follows :—■ 
Row No. 1.—Myatt’s Ashleaf. 
„ „ 2.—Snowdrop. 
„ „ 3.—Beauty of Hebron. 
„ „ 4.—White Elephant. 
„ „ 5.—Carters’ King of the Russets. 
„ „ 6.—Carters’ Cosmopolitan. 
,, „ 7.—Carters’ Improved Magnum Bonum. 
„ „ 8.—Bruce. 
,, ,, 9.—Carter’s Surprise. 
„ „ 10.—Imperator. 
The whole piece was divided into four equal parts, of which 
the first and third were dressed with the Bouillie Bordelaise, and 
the second and fourth left undressed. The strength of the mixture 
was as follows :— on , , , , , 
22 lb. of sulphate of copper, 
22 lb. of unslaked lime, and 
100 gallons of water ; 
this being the quantity necessary for an acre of Potatoes. The 
sulphate of copper is of 98 per cent, purity, and is the Macclesfield 
patent sulphate of copper, this being the same as that used by 
M. Aime Girard in his experiments. For the purposes of the 
experiment the first and third quarter were dressed with the 
Bouillie Bordelaise on July 11th and August 2nd, and the second 
and fourth left undressed. The mixture was applied by the 
Antipest, the new knapsack distributor, invented by Mr. G. F. 
Strawson, which did the work admirably. On the second occasion, 
a German machine was also tried, this also doing good woik. 
During the period of the experiment the weather has been 
as follows :— 
April 8th to 30th.—R ainfall: 150 inch (on ten days). The rain fell 
on continuous days from 24-25th to 28-29th (0'55 inch). 
Frost was registered on thirteen occasions from April 10th to 30th, 
in intensity ranging from 1° to 7°. 
Severe snowstorm 1 A.M. to 8 A.M. April 16th. 
May. —Rainfall P46 inch (on ten days). Very little rain (0 21 inch on 
eight days) until after the 24-25th ; and on the 25-26th there was 
registered 0 - 97 inch. 
Frost registered on May 1st (5°), May 7th (4°). 
June. —Rainfall 2 64 inches (on fourteen days). Thunderstorm 28th 
8.30 p.m. to 11 p.m. Thermometer, lowest, 35° ; highest, 98°. 
July. —Rainfall 2 53 inches (on eight days). Very severe thunder¬ 
storm on the 14th, 1015 a.m. and 12.30 midday, when 0'90 inch of 
rain fell. Thermometer, lowest, 39° ; highest 90°. 
August. —Rainfall 3'35 inches (on sixteen days) ; the heaviest fall was 
27-28th, 0 - 98 inch. Thermometer, lowest, 38° ; highest, 98°. 
September 1st to 14th.—R ainfall 0-57 inch (on seven days). Ther¬ 
mometer, lowest, 35° ; highest, 83°. 
Early in this month (September) it was clear that disease had 
appeared in the undressed portions, and on September 6th one 
root was dug from the centre of one row of each variety in the 
first three sections. In the dressed sections only two diseased 
tubers were found in the twenty roots dug, and those were in the 
one root of Myatt’s Ashleaf. On the other hand, of the ten roots 
dug in the section not dressed, in four cases all the produce was 
found to be diseased, in two cases slightly diseased, in one case 
very slightly diseased, and in only three cases—The Bruce, Carters’ 
Surprise, and Imperator (vigorous growers)—was the produce 
found to be all sound. In other words, 90 per cent, in one of the 
dressed sections and 100 per cent, in the other dressed section were 
found to be all sound and good produce, and in the case of the 
undressed section only 30 per cent, were sound. 
On Thursday and Friday last the crops were dug, when the 
following were found to be the condition and weights of the diffe¬ 
rent varieties of Potatoes on the four quarter plots :— 
First Quarter Plot.—Dressed. 
Row and variety. 
Weight of 
sound tubers 
Weight of 
diseased 
tubers. 
Total. 
cwt. 
qr. 
lb. | 
cwt. qr. 
lb. 
cwt. 
qr. 
lb. 
1. 
Myatt’s . 
3 
1 
5 
— — 
li 
3 
1 
6* 
2. 
Snowdrop. 
2 
2 
12 
- - 
If 
2 
2 
13f 
3. 
Beauty of Hebron ... 
2 
3 
18 
- - 
n 
2 
3 
20J 
4. 
White Elephant . 
3 
2 
19 
- - 
2 
3 
2 
21 
5. 
King of the Russets... 
3 
3 
14 
none 
3 
3 
14 
6. 
Cosmopolitan . 
2 
2 
7 
— — 
o* 
2 
2 
7i 
7. 
Magnum Bonum. 
3 
2 
19 
none 
3 
2 
19 
8. 
The Bruce. 
4 
0 
0 
none 
4 
0 
0 
9. 
Carters’ Surprise. 
3 
2 
10 
none 
3 
2 
10 
10. 
Imperator. 
4 
3 
10 
none 
4 
3 
10 
Totals . 
35 
0 
2 
— — 
8J 
1 35 
0 
10* 
No. 2295.— Vol. LXXXVII., Old Series. 
