Boebera 



( 129) 



Boletus 



Principal Species : 

 clarkeana, t>", sum., grh. 



ferruginea. <>", sum., st. 

 hvgrnmetrica, (>", sum., grh., pale bl. 



BCEBERA. 



A small genus of Composites (ord. Compositse), 

 by must authorities referred to Dysodia, with small 

 or medium sized beads of yellow flowers, and 

 deeply divided leaves. Annuals increased by seeds, 

 pnviiriials by division. Light sandy loam and leaf 

 mould will suit them. 



Principal Species : 



chrysaiithcnmiil.'s, U', inoana, 1-i', Nov., grh. 

 Oct., Inly. aim. (//. Dysodia pubes- 



ceus) . 



BCEHMERIA. 



.Mostly tall herbs (onl. Urticacea?), notable for 

 the libre in their stems, used for textile purposes. 

 The most important is the China Grass or Rhea 

 fibre plant (nivea). They are propagated by 

 division, and the hardy ones are of easy cultivation 

 in any garden soil. 



Principal Species : 



(ylimlrica, 4', Je., Aug., 



Inly., grn. 



c-li'ti'jatu, 4', Inly., grn. 

 latenflora (set- cylindrical). 

 nivea c'itndioaiis, 6', hdy., 



grn. 



ramittora, Feb. to My., 



st. shr., grn. 

 rubesceus ( Villebrunea 



rubescens) . 

 tonaciasima (sec nivea 



candicaus) . 



BOILERS. 



IV. -d for the purpose of heating glass structures, 

 the boiler being the receptacle which holds the 

 water and is brought into direct contact with the 

 lire Since the introduction of hot water for 



PLAIN SADDLE BOILER. 



heating purposes, boilers have received careful 

 attention at the hands of engineers, with the 

 result that many powerful and ingenious con- 

 trivances are now in use. In all the improvements 

 made, the main idea has been to expose as much of 

 the surface of the boiler to the fire as possible. To 

 effect this purpose, tubular boilers, composed of a 

 series of tubes holding water, have come largely into 

 use. The capacity of a boiler is dependent on the 

 amount of surface space exposed to the fire. 



Horizontal Boilers. These apparatuses are fixed 

 horizontally with the fire space, mostly under- 

 neath, and fed from the front. The plain 

 saddle, having horseshoe sha]>ed, open ends with a 

 lire cavity underneath, is the simplest form of 

 horizontal boiler ; but it has undergone many im- 

 provements, in the way of waterway ends, ret.urn 

 fines through the crown, and water tubes substi- 

 tuted for the phain sides and crown. Saddle 

 9 



boilers of different sizes are suitable for heating 

 both small and large structures. A powerful 

 horizontal boiler is the Cornish Trentham, which 

 is like a large cylinder, with the fire in the centre 

 of the boiler. It is excellent for heating long 

 ranges. 



Upright Boilers. These are mostly made on the 

 tubular principle, and are fixed perpendicularly. 

 Powerful appliances of this kind are used for the 

 heating of long ranges of piping, and are generally 

 fed from the top by means of a funnel. 



Independent Boilers. Not the least important 

 among boilers are the appliances made for heating 



SADDLE BOILER WITH WATERWAY ENDS. 



the small greenhouses and conservatories of 

 amateur gardeners, and in the making of these 

 a large amount of ingenuity is displayed. Of 

 these apparatuses there is a great number on the 

 market, made on different plans but with-, the 

 same objects in view. They are fixed in position 

 without the need of stoke-holes or brickwork, and 

 may be readily removed. They are so arranged as 

 to burn and maintain heat for a long time without 

 much attention, while they effect the purpose of 

 warming a small house adequately, without the 

 danger of the water boiling and turning into steam. 

 To meet the requirements of the amateur still 

 further, heating apparatuses on the boiler prin- 

 ciple are made, for the working of which oil and 

 gas are used as fuel, and they are suitable for 

 warming very small structures. Though the 

 simplest of boilers do their work satisfactorily if 

 properly fixed, the improvements on the types are 

 quicker in action, and generally more economical 

 in the way of fuel. (See a/so HEATING.) 



BOLETUS. 



A genus of some forty-one British species of fungi 

 (ord. Fungi), with the habit of an Agaricus or 

 Mushroom, but differing remarkably in the form 

 of the hymenium or spore-bearing surface. This 

 ronsi.-ts of numerous slender tubes, open at the 

 round or angular mouth, and closely packed, but 

 readily separable from one another. The spores 

 are produced on the inner face of these tubes. 

 The species grow upon the ground, and are mostly 

 edible, but a few poisonous. The latter may 

 readily be distinguished by the red mouth of the 

 tubes. Although experts eat the greater number 

 of the species, only a very few are in any way 

 popular. Some of the most highly appreciated are 

 edulis, lutens, fragnuis, impolitus, aistivalis, and 

 scaber. 



(sec Menyanlhi'x tfifuliata). 



llitylitii a */v Mtiiyatt 

 Jioldea (see Peiiiuui). 



