ABSTRACTS
A note on the inheritance of kemp in black-face sheep. D. M. BRYANT
(1933). J. Textile Inst. 24, T 309
T HE term ' kemp ' is applied to the opaque fibres, occurring in the outer coat of
the primitive sheep. It is much coarser than the other fibres and, owing to the
presence of an air-filled medulla, has a dead white appearance. The fibre is very brittle,
possesses a marked wave in one plane only and very low tensile strength. The presence
of these fibres in wool is a matter of deep concern both to the breeder and the trade. To
the breeder it means depreciation in the value of the fleece and as for the
manufacturer of woollen materials he can utilise the low quality wool for coarsest fabrics
only. No method of removing the kemp is available except the laborious one of hand-
picking. Fortunately the fine woolled sheep are mostly free from kemp but in some of
the other breeds, e. g. Cheviot, it is responsible for considerable wastage. Investiga-
tions were undertaken by the author to ascertain the possible mode of inheritance of kemp
and the breed chosen for this purpose was the Scottish Mountain Blackface. The experi-
mental sheep were kept under standard commercial conditions from year to year, which,
obviously, could not be controlled.
The experimental evidence has shown that there is a hereditary basis for the expres-
sion of kemp in the fleece and that it is influenced to some extent by the system of feeding.
Like other wool fibres, kemp also responds in thickness and rate of growth in length to
altered conditions of feeding, and due to its greater original thickness and marked cons¬
picuousness in the fleece, better nutrition leads to apparently greater increase in the
amount of kemp visible in the fleece on the living sheep. Thus these results lead to the
conclusion that if an endeavour is to be made to reduce the amount of kemp in wool,
attention should be devoted primarily to the manipulation of the breed constitution
rather than the environment of the sheep.
In the present investigation the analysis of samples from parental and filial genera-
tions has shown that kempiness in the fleece is inherited, that rams with fleece
containing less than 1 per cent of kemp leave greater numbers of progeny which
approximate to this figure than do more kempy rams and, lastly, that it is possible to
produce a flock with low kemp content by using rams of less than 1 per cent of kemp and
eliminating the kempy sheep.
[H. B. S. ]
The improvement of Chinese and other carpet wools. R. H. BURNS
A. JOHNSTON and W. C. CHEN (1940). J. Textile Inst. 31, T 37
I N this article, the authors have formulated a tentative guide of wool type for carpet
wool producers. The characteristics and origin of some of the different types of
carpet wools have been described and opinions of the trade in respect of the relative values
of different samples of desirable and undesirable carpet wools have been recorded. It is
common knowledge that carpet wools are obtained from sheep reared under primitive
conditions in various parts of the world. With the exception of a few thin-tailed varieties,
most of this wool comes from the fat-tailed and broad-tailed varieties of sheep in Asiatic
countries. The type of fleece in these sheep is composed of a mixture consisting of a
long hairy outer coat, a finer undercoat and true wool and a third type of fibre, the so-
called ' kemp '. The outer coat consists of heterotypical fibres, i. e. hair and intermediate
fibres. As the name implies, these fibres are neither wool nor kemp. Originally this
designation was confined to those fibres which within the same shaft showed characteristics
of wool fibres, kemps and hairs. Now it is restricted to those fibre shafts which possess
the characteristics of both wool and hair in the same fibre, particularly in respect of medul¬
lation and non-medullation. True wool consists of fibres which form the fine under-
coat of the mixed-wool sheep. Kemps are the brittle fibres which lie loose in the fleece.
These are not normally shed. In the present investigation the authors have analysed
both microscopically and macroscopically seven samples of carpet wools and a sample of
Romney wool for fibre types, fibre thickness and fibre length. They have observed that
the Vicanere and Aleppo wools are considered the best carpet wools in the world by carpet
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