36 



CASSELL'S POPULAR GARDENING. 



female, as it is sometimes lost. It is bright green in 

 colour, but in strong light turns nearl}^ red. The 

 female flowers have long stalks, and reach the 

 surface of the water, and are curiously pollenated by 

 the breaking away of the male flowers from the base 

 of the plant ; they theoi float to the surface and are 

 wafted to the females. It is a native of Southern 

 Europe, and is found in the Lakes of Ticino in 

 Switzerland. Another species is found in Australia. 

 Hydi'ocharidece. 



Victoria Regia (the Royal Water-lily). — This is 

 well known as the most magnificent of aquatics, and 

 as forming one of the great attractions at Kew and 

 Regent's Park every summer. Its immense foliage 

 and lovely gigantic flowers entitle it to all admira- 

 tion. The leaves are usually about six feet in 

 diameter — sometimes six feet eight inches — with a 

 bold turned-up margin, and the flowers measiu-e 

 about one foot, or even fifteen inches in diameter. 

 They first open late in the afternoon, and are then 

 pure white, afterwards turning to a dark rose-colour 

 In order to secm^e seeds, the fruits when ripening 

 must be enclosed with canvas, and they require to be 

 kept in uncorked bottles of water. The best time 

 for sowing is about the 1st of January; if sown 

 earlier the plants suiier duiing the dark days of 

 winter, and success is attained only by growing the 

 plants without check from the first ; if they are sown 

 later than the above date, time is lost. The young 

 l^lants must be shifted without injury to the roots 

 till they reach 24-sized pots, which will be about the 

 third week in April, when they are ready for planting 

 out. A mound of soil is made in the centre of 

 the tank, reaching to about eight inches from the 

 highest level of the water, when the plant is 

 developed. Success equal to any I know has been 

 attained with about five cart-loads of soil, composed of 

 loam ten parts, horse and cow manure one part, and 

 peat and sand one part, but in the place of the peat 

 I should use leaf-mould. Richer soil than this, 

 however, is often used. At first the water should be 

 a little more than one inch above the crown of 

 the young plant, and as it grows the level of 

 the water is raised. It is convenient to raise young 

 plants every year, but the Victoria is not an annual, 

 and it has been made to flourish in Paris for three 

 years. The water should be kept at a temperature of 

 85'', and a fresh supply must be let in every day. 

 Air must be given freely, but with caution, in 

 order to avoid chill. This plant varies in some 

 particulars, and it would be interesting to get 

 seeds from various localities, as it is possible 

 that distinct forms might be obtained. The 

 seeds are roasted and eaten. Native of the Amazon 

 basin, and of the rivers of Guiana and La Plata. 

 NymphcBacece. 



MANUEING m THEORY AND 

 PRACTICE. 



By Johx J. Willis. 



PREVIOUS to the middle of last century, 

 chemistry as a science can hardly be said to 

 have had existence, so we may fairly conclude that, 

 prior to that date, horticulture as an art, whatever 

 assistance it may have received from other som-ces, 

 was prosecuted independently of any aid fi-om 

 chemical science. During the last fifty or sixty 

 years, however, chemistry has applied much of its 

 force to the investigation of the constituent elements 

 of the organised bodies of plants, and to an exami- 

 nation of the processes which go on in them during 

 their life. Of what do these bodies consist r Whence 

 do they acquii-e their component parts and then- 

 sustenance ? What changes must the latter under- 

 go in the living organisms of the plants in order 

 to peld them nourishment and produce growth ? 

 Whence are we to draw our supply of those agents 

 which, according to our present ideas, are destined 

 to become the principal lever of horticulture ? 



These are some of the main inquiries which, by the 

 aid of modern chemical research, we shall endeavour 

 to answer, and from observations and experiments 

 made in the field and in the laboratory, to deduce 

 principles which may be more or less applicable to 

 the requirements of the practical gardener. 



Such piinciples, we trust, will explain useful 

 practices and confirm their propriety. They will also 

 help to account for contradictory results, and will 

 point out the circumstances under which this or that 

 practice may most prudently and most economically 

 be adoj)ted. Armed with the knowledge of such 

 principles, the gardener will go among his j)lants as 

 the physician goes to the bedside of his patient- 

 prepared to understand s^-mj^toms and appearances 

 more clearly than he has done before, and to adopt 

 his practice to circumstances which have never 

 before fallen under his observation. 



There is a sajdng, somewhat common among those 

 who aflPect to despise or contemn chemistry as a help 

 to the horticulturist, to the effect that " a chemist 

 would make a very poor gardener." Very possibly 

 this is true, but as well might it be said that an an- 

 atomist would make but a poor physician ; or that any 

 man possessing one only of the several qualifications 

 necessary for any occupation in life would be but 

 poorly fitted for fulfilling the duties of that occupa- 

 tion. If a man is purely and simply a scientific 

 chemist, the chances are that he would most likely 

 make a very unprofitable business of gardening : and 

 yet Lavoisier, who had certainly no very minute 

 knowledge of the art of husbandry, by following a 



