Chap. XXX.] MUSHROOM-CULTURE IN CAVES UNDER PARIS. 513 



a Mushroom-grower would never answer here, as the little bud- 

 ding " buttons " are watched every day. The average daily 

 gathering from this cave is about 880 lbs. weight, and some- 

 times that is nearly doubled. Even when the crops reach their 

 lowest ebb, about 400 lbs. per day are sent to market. The 

 proprietors of the larger quarries are coming to the conclusion 

 that culture on a more limited scale gives the best return in pro- 

 portion to expense, the care and supervision required by so many 

 miles of beds being too great. 



All the manure employed is brought from Paris by rail, as the 

 place is twenty-five miles from that city by road. In the first 

 place, so much per horse per month is paid in Paris for the 

 manure ; then it has to be carted to the railway station and 

 loaded in the waggons; next it is brought to the station of 

 Auvers, and afterwards carted a couple of miles to the quarries, 

 paying a toll for a bridge over the Oise on the way. One grower 

 at Mery-sur-Oise uses as much as 300 tons per month. It is 

 placed in large flat heaps a yard deep by about thirty long and 

 ten wide, not far removed from the mouth of the cave, and here 

 it is prepared, turned over and well mixed three times, and as a 

 rule watered twice. About five or six weeks are occupied in the 

 preparation, long manure requiring more time than short. The 

 watering is usually limited to parts where it is dry and overheated. 

 Every day stable-manure is brought from Paris ; every day new 

 beds are made and old ones cleared out — the spent manure, useless 

 in Mushroom-culture, is much in demand by farmers and gardeners, 

 it being very useful for garden-purposes, particularly in surfacing 

 or mulching. The advantage the cultivator has in these caves as 

 compared with the mine-caverns near Paris, is the taking his 

 materials in or out in carts, as easily as if the beds were made in 

 the open air. Many men are employed in the culture here, the 

 daily examination of so large an extent of beds being a consider- 

 able item in itself. Here and there a barrier in the form of straw 

 nailed between laths may be seen blocking up the great arch- 

 ways to a height of six feet or so. This is to prevent currents 

 of cold air wandering through the vast passages. 



The mode of preparing the spawn here is entirely different to 

 ours. The French growers prefer virgin spawn — that is to say, 

 spawn found naturally in a heap of manure. But as this material 



