June 1, 1865.] THE TECHNOLOGIST. 



THE KOLA-NUT. 515 



the whole of the machinery, consisting of sawing-, planing-, scraping-, 

 and polishing-machines iu motion. 



The manufactory, however, not only embraces the production of 

 writing-slates, but works the slate into the most varied forms. The 

 rough slab of slate which was formerly used for flooring, without any 

 finer manipulation, will now decorate the most elegant saloons in the 

 form of handsome marble ; the simple slab forming the peasant's table 

 will now be converted into an elegantly wrought work of art. The 

 most ingenious work now finds a rival in the humble slate, which being 

 used for washing-stands, chess- or card-tables, will prove an excellent 

 imitation of the finest mosaic work. Silver and mother-of-pearl will 

 ornament these articles, the colours of which are unchangeable, while 

 their polish is of an indestructible hardness and brilliancy. 



If thus a new and rich field is opened for comfort, enjoyment, 

 luxury, and the ornamental, the useful, on the other hand, is also repre- 

 sented and combined with the ornamental in the chief business of the 

 manufactory, the production of an excellent writing slate. To the 

 attentive observer the new article at once evidences progress and per- 

 fection. The smoothness of the surface of the slates leaves nothing to 

 be desired ; while their uniform dark colour causes the writing to stand 

 out very plainly, and their softness allows of a stroke of any quality from 

 the thickest downstroke to the finest upstroke. They are also ruled in a 

 manner in exact keeping with their size and the various branches of 

 education, as also with the requirements of household and commercial 

 life. The frames, some of soft wood, some of hard, are well, durably, 

 and tightly jointed together, considerably diminishing the chance of 

 breaking the slate ; finally, a coating of varnish protects the wood from 

 becoming dirty ; and even the ornamental is not lost sight of, as they 

 are decorated with small and tasteful arabesque devices. 



THE KOLA -NUT OF TROPICAL WEST AFRICA.— (THE GURU- 

 NUT OF SOUDAN.) 



BY W. F. DANIELL, M.D., F.L.S. 



It would probably prove a futile task to attempt the discovery, through- 

 out the vegetable kingdom of tropical West Africa, of any analogous 

 product that occupies such an exalted position in the social or dietetic 

 economy of the negro tribes, or constitutes such an important article of 

 traffic in Soudan, as the seeds of the Kola-tree {Cola acuminata, R. Br.). 

 With the majority of the aboriginal races populating that vast extent of 

 territory comprehended between Senegambia to the north, and the pro- 



