310 THE FLORAL WORLD AND GARDEN GUIDE. 



green or bluish green patches of another iron compound containing 

 sulphur are also seen spreading over the surface of the gravel. 



In spreading a layer of gas-lime as a bed for new gravel to be 

 laid upon, care should be taken that the thickness of this layer does 

 not amount to one inch at most ; and in emptying carts of it in the 

 garden, the heap should be placed at a great distance from valuable 

 trees or shrubs ; for not only does its poison sink into the ground 

 with the rain, but a considerable amount of sulphuretted hydrogen 

 gas is constantly evolved from it, and this gas is also highly poisonous 

 both to animals and plants. 



Laboratory of Analytical Chemistry, Putney, S.W., Sept. 1869. 



CULTURE OP THE MUSHROOM. 



UN an elaborate article in the Field, Mr. Robinson reviews all the methods 

 practised and recommended in the cultivation of the mushroom, and 

 ai rives at the following conclusions : — 



1. That very careful pieparation and frequent turning over of the 

 manure under cover are not necessary to success, and that it is quite 

 needless to prepare the manure under cover except when it is gathered in very 

 small quantity, so that a heavy rain or snow would saturate it. But, as it is in 

 the earlier autumn months that it is generally gathered for mushroom beds, there 

 is usually little need of putting it under cover. 



2. That carefully picked droppings are not essential, though they may be more 

 convenient. Excellent crops are gathered from beds made with ordinary stable 

 manure, droppings and long materials mixed as they come ; but when the manure 

 is used as it comes from the stable, it should be allowed to ferment before being 

 used. 



3. That the best way of preparing manure for the general culture of mushrooms 

 indoors is to gather it in some firm spot, and allow it to lose its fierce heat. As it 

 is usually gathered in an irregular way, precise directions as to turning over cannot 

 well be given ; but we are convinced that one turning will suffice when it has 

 arrived at a strong heat, and then it should be thrown together for a week or so, 

 when, in being disturbed and removed to make the bed or beds, its strong heat will 

 be sufficiently subdued. Where large quantities of stable manure are in a ferment- 

 ing state, there should be little difficulty in selecting material to form a bed at any 

 time. Should it have spent its heat overmuch, it would be easy to vivify it with 

 some fresh droppings. 



4. That stable manure may be used when fresh, but that it should be used as 

 short and as dry as possible, and then always mixed with more than a fourth of 

 good loamy soil. If this be kept under cover, or stacked so that it may be had in 

 rather a dry condition, so much the better, especially if the fresh manure, etc., 

 should be too moist. Beds made thus are most suited for cool sheds and the open 

 gardens. 



5. That a portion, say nearly one-fifth to one-third, of good and rather dry 

 loam may always be advantageously mixed with the stable manure ; the fresher 

 the materials, the more loam to be used. In all cases it. helps to solidify the bed, 

 and it is probable that the addition of the loam adds to the fertility and duration 

 of the bed. 



6. That a thickness of one foot for the beds in an artificially heated house is 

 quite sufficient. Fifteen or eighteen inches will not be too much for beds made in 

 sheds, though we have seen excellent crops on beds only a foot thick iu common 

 sheds with leaky sides. All beds made indoors should be flat and firmly beaten 

 down, though the absence of firmness is not, as some think, sufficient to account 

 for want of success. 



