122 Abstract Report on Rot in Sheep. 
the summer of last year. It was at that time, and more espe- 
cially in the months of July, August, and September, that in 
consequence of the excessive fall of rain saturating the ground 
with wet, and producing the overflow of streams and rivulets, 
that the fluke-embryos in vast numbers were taken in with the 
food of the sheep. Had agriculturists then adopted means, 
which were pointed out as far back as 1862, to prevent the 
embryos, thus widely dispersed, developing into young flukes 
within the organism of the sheep, hundreds of animals now 
falling a sacrifice to rot would have been saved. 
These and other important and kindred facts connected with 
the parasitic origin of the disease and its prevention were set 
forth in an Essay on Rot, which was published originally in the 
Society's ' Journal,' in 1862, and is now republished in a sepa- 
rate form, with extensive additions, for circulation among 
agriculturists in general.* 
It is well known that in many valley farms and wet feeding- 
grounds sheep will take the rot in any year, be the state of the 
weather what it may ; but the whole history of the disease from 
the earliest times, as well as all recent investigations into the 
natural history of the liver-fluke, show that in wet summers 
danger is incurred by the pasturing of sheep on land which 
under ordinary circumstances Avould be safe. Outbreaks equally 
as extensive and fatal as the present have occurred in this 
country in past years ; and, dating back to 1735, the following 
periods may be quoted as examples : 1747, '66, '92, 1809, '16, 
'24, '30, '53, and '60. Ireland also suffered to a most serious 
extent in 1862, when wet weather prevailed there throughout 
the year ; but in England, on the contrary, the summer being 
dry, only partial occurrences of the disease were observed, 
especially on wet and boggy pasture land. 
The rot of 1830-1 is believed to have been the most serious 
outbreak of any recorded, evidence of the destruction of not less 
than two millions of sheep having been given before a Pailiament- 
ary Committee, which sat in 1833 to inquire into the causes of 
the depressed state of agriculture. The rot of 1860 also swept 
away thousands of sheep, and affected large numbers of cattle, 
the year having been, like the past one, remarkable for the 
almost uninterrupted rainfall for weeks together. So long as 
the weather continues warm and humid into the autumn, so 
long does great danger exist ; but a change from wet to dry, 
and especially the occurrence of sharp frosts, speedily arrests 
the development of the fluke-embryos. 
* ' The Eot in Sheep : its Nature, Cause, TreatBient, and Prevention.' Illus- 
trated with Engravings of the Structure and Development of tlie Liver-fluke. 
By James Beart Simonds. London : John Murray, 1880. Price 6d. 
