H V S 
H U S 
tt Y D 
9<5 
Such land is often too light for wheat. \\ here' 
barley is elnploy eel, grass seeds are frequently 
sown with it, but it is probably a better prac- 
tice to put them in separately. On those 
soils, rye-grass, as well as white and yellow 
clover, have been found to thrive extremely 
well, especially where they were in a proper 
stale of preparation for them, as by the 
growth of potatoe or turnip crops. And 
though red clover has not always succeeded, 
it is probable, that in such mosses as are not 
of the deep kind, it will he found an useful 
plant. In some districts it has been found 
that clover may be sown with great advan- 
tage immediately after the pdtatoe crop, when 
it has been taken off early. 
It. is evident, from what has been advanc- 
ed, that as there is much variety in soils of j 
this kind, they wall of course require different | 
modes of tillage. W Imre they are very thin, j 
and deposited upon a loamy or clayey sub- j 
stratum, it may be a good practice to plough 1 
so as to bring up a portion ot them, by which, 
and the use of lime, the land may be rendered 
highly productive. 
'Ploughing, This, or some other method 
of loosening and turning up the superior parts 
of soils, is constantly requisite in order to 
render them suitable for the reception ot the 
seed or crop that is to be cultivated. It is 
by means of this kind that a convenient bed 
for the roots of the young plants, and a pro- 
per condition of the land for supplying them 
with due nourishment, is in a great measure 
provided, as well as a proper state of dryness 
in many cases afforded. 
There are certain circumstances that con- 
stantly demand notice in the practice of 
ploughing land. I 11 all the stiff, heavy, and 
more adhesive kinds of soils, that are much 
disposed to the retention of moisture, whe- 
ther they be perfectly clayey, or have more 
of a loamy quality, it should be a common 
rule never to plough or turn them up when 
wet in any great degree, except w’liere the 
nature of the crop requires it. And further, 
great injury is produced by the treading ot 
the team, as well as a much greater power 
necessary in performing the operation. But at 
the same time they should not be permitted 
to become so dry and hard as to afford too 
great resistance in that way, before the opera- 
tion is proceeded upon. 
But in the dry, sandy, and probably in 
some of the more mellow and friable kinds ot 
loamy soils, the business of ploughing, espe- 
cially for the putting in of the seed, may be 
performed when they are in a state of consi- 
derable moisture, not only without their suf- 
fering any inconvenience, or the seed being 
injured, but often with advantage, as they are 
liable to part with the watery particles that 
they contain too readily. On this last ac- 
count the very dry sorts of sandy land should, 
whenever the weather is hot and dry, merely 
be stirred in such way as may be necessary to 
prevent the growth of weeds, otherwise the 
great exhalation of moisture in such seasons 
may render them too dry for the healthy ve- 
getation of the seeds or plants that may be 
sown or set upon them. 
In regard to the depth and frequency of 
ploughing lands, they most constantly de- 
pend, in a great measure, upon the qualities 
and die sorts of crops that are to be grown. 
But in general the different preparatory 
ploughings should be deeper than those of 
Yol.I. 
I lie seed furrow, which ought mbstly lobe 
light, and the slice not too much laid over, 
that the seed, especially where the broad-cast 
method of sowing is adopted, may be the 
more perfectly covered. 
Upon all light soils it is necessary to pre- 
serve, at six or eight inches below the sur- 
face, what farmers call a pan; that is, the 
staple, at that depth, should be kept unbroken; 
by which means manure will be kept longer 
on the top: and in dry seasons the less depth 
the pan has, the less liable the corn will be 
to burn, provided the pan consists of earth, 
and not of rock; because the roots of the 
corn will lind more moisture by striking 
against a body of close earth than they will in 
a greater depth of hollow earth ; as it is evi- 
dent the former preserves more moisture in 
dry seasons. 
In regard to the frequency of ploughing or 
turning over ground, in order to prepare and 
render it suitable for the production of good 
crops, it is obvious there must be much dif- 
ference according to the nature and condition 
of the soil, as well as the kind of crop that is 
to be grown. T he stiff, clayey, loamy, and 
1 even chalky soils will, in general, stand in 
need of more frequent stirring, either by 
means of the plough, drag, or harrow, in 
order to separate and break dow n their tena- 
cious particles, than those of the sandy or 
gravelly, and more light kinds, in which there 
is much less adhesion. Besides, w here lands, 
have been in a course of tillage tor some 
length of time, whether they are of a clayey, 
loamy, or even sandy quality, they may re- 
quire' less frequent stirring than., w here the 
contrary is the case. And w here the method 
of putting the seed into the ground by means 
of drill machines is to be had recourse to, a 
fine state of tilth will, in general, lie indispen 
sably necessary. 
The nature of the crop that is to be culti- 
vated must, however, in most cases, direct 
the number of ploughings that may he ne- 
cessary, as some demand a much liner state 
of tillage than others; though in most cases a 
well-reduced earth is favourable. 
In the choice of implements for the per 
formance of this business, tire agricultor 
should lie careful that they are well suited to 
the nature and quality of the land, as it is 
not possible that any particular sort ot plough 
can be employed with equal facility and ad- 
vantage on soils of every description. T he 
more stiff and heavy kinds of land will require 
ploughs of more strength than those ot the 
thin chalky, and a light, sandy, or gravelly 
nature. The former may mostly be managed 
in a proper manner by any ot the well-con- 
structed kinds of strong ploughs; as the So- 
merset single-wheel plough, the Hampshire 
two-wheel plough, and the latter by those ot 
the light sort, as the Rotheram plough, the 
Norfolk light two-wheqled plough, or the 
double-furrowed plough. See Plate, Ploughs, 
See. But whatever description >«f plough 
may be had recourse to, it is a matter ot the 
greatest consequence that it be .properly 
formed and attached to the draught, as where 
these points are not minutely attended to, 
there must .constantly be a considerable loss 
in the economy ot labour and time, as well 
as in the compfeutness of the work. 
HUSK, the same with what botanists call 
Ike calyx, or cup of a ilower. See Calyx. 
HD 
HYACINTH, in natural history, a genus 
of pellucid gems, whose colour is red with an 
admixture ot yellow. See Zircon. 
HYACINTHUS, a genus of the mono- 
gy ilia order, in the hexaudria class of plants, 
and in the natural method ranking under the 
10th order, coronariau The corolla is cam- 
panulated, and there are three melliferous 
pores at tiie top of the germen. 1 here are 
1 17 species, of w hich the most remarkable is 
| the oriental is, or eastern hyacinth. Ot this 
there are a great number of varieties, amount- 
ing to some hundreds, each of which differs 
from the rest in some respect or other. 
These plants are cultivated with the 
greatest success in Holland, whence great 
numbers are annually imported into Britain, 
Each variety is by the llorists distinguished 
either by the name of the place where first 
raised, or the person who raised them, or the 
names of illustrious personages, as ot kings, 
generals, poets, and celebrated undent histo- 
rians, gods, goddesses, &c. They are sold 
by all the seed-dealers. The prices are from 
3d. per root to 31. or 10/. or more; and some 
varieties are in such high esteem among the 
llorists, that 20/. or 30/. will be given for a 
single bulb. They are hardy, and w ill pros- 
per any where, though the tine kinds require 
a little shelter during the winter. They may 
be propagated either by seeds or olf-sets from 
the roots. 
I1YADES, in astronomy, seven stars i* 
the bull’s head, famous among the poets foe 
the bringing of rain. The principal ot them 
is in the left eye, called by the Arabs Aide* 
baran. 
HYALITE, in mineralogy, a stone fre- 
quently found in trap rocks. It occurs in 
grains, filaments, and rhomboidal masses. 
Texture foliate. Fracture uneven, inclining 
to conchoidal; sometimes opaque; specific 
gravity 2.11; colour pure white. Infusible 
130° Wedgewood, but it yields to soda. Ac- 
cording to Mr. Link it is composed ot' 
57 silica 
18 alumina 
15 lime 
90 and a little iron. 
HYDATID ES, in medicine, little tran- 
sparent vesicles or bladders, full of water, 
sometimes found solitary, and sometimes in 
clusters, upon the liver., and various other 
parts, especially in hvdropical constitutions, 
oee Medicine. 
HYDNUM, a genus of the natural order 
of fungi, in the cryptogamia class of plants. 
The fungus is echinated or prickly on the 
under side. There are six species. One ©f 
them, named the imbricatum, is a native of 
Britain, and is found in the woods. It has a 
convex hat, tiled, standing on a smooth pillar, 
of a pale llesh-coLour, with white prickles. It 
is eaten in Italy, and is said to be of a very 
delicate taste. 
HYDRA, in astronomy, a southern con- 
stellation imagined to represent a water-ser- 
pent. The number of stars in this constella- 
tion in Ptolemy’s catalogue is 25, and in the 
Britannic catalogue OS. 
HYDRA, a genus of vermes zoophyte. 
The generic character is, animal fixing itself 
by the base, linear, gelatinous, naked, con- 
tractile, and furnished with setaceous tenta- 
cula, inhabiting fresh waters-, and producing 
