A CHEMIST'S HOLIDAY IN FRANCE. 



437 



Brian?on 

 manna. 



kernels, which yield by expression a fatty oil, considered by the 1864 

 peasants a useful medicine both for man and beast. I bought 

 some of it, and found it to have an agreeable flavour and a 

 slight odour of bitter almonds ; further than that it was " trte- 

 lonne pour la colique" I could not gain any very definite idea as 

 to its virtues. 



Briangon, however, has another pharmaceutical interest, in 

 the manna which old writers relate is, or can be, collected from 

 the larches that grow in its vicinity. The larches certainly are 

 there, and very interesting it is to see them growing truly wild 

 on their own native mountains. 



During a visit to Brian9on in June 1857, I made particular 

 examination of the larches on the neighbouring hills, and 

 obtained so little evidence of anything like saccharine exudation 

 that I was ready to conclude the formation of such a substance 

 must be of rare and exceptional occurrence. Subsequently to 

 this, however, M. Berthelot, of Paris, actually made a chemical 

 examination of Brian^on manna, and demonstrated it to contain 

 a peculiar variety of sugar, which he designated Melezitose, a Melezitose. 

 name derived from meUze, the French for larch. 



Here again in the country of the larch and in the very Larch Manna, 

 classical locality for the manna it was necessary of course to re- 

 new the previous fruitless research, and my travelling companion 

 felt equally interested in the inquiry. A day or two before we 

 reached Briangon, we had examined larches at La Grave a few 

 miles distant, but not a trace of saccharine exudation could we 

 discover. There was a little white aphis on the leaves of several 

 trees, just as one often sees upon the larch in England ; and 

 upon examining the insect carefully, one could perceive a minute 

 globule attached to one part of it. Was this the manna ? or had it 

 anything to do with it ? Here was a globule of something, but too 

 small to collect, or even to taste per se : still in our desperation 

 we licked the aphis-coloured leaves, and fancied they had a faintly 

 saccharine taste. The cones certainly had an exudation, but it 

 was turpentine to all intents and purposes, fine clear drops of 

 genuine Venice turpentine ; and a botanist of Briangon assured 

 us a day or two after that this was the manna. As I could not, 



