On Aerial Navigatioyi . 1 97 



Barley and rye, or barley and wheat, in equal proportions. 

 The last is equal to the best bread of vvheaten flour alone. 



Buck-wheat. 



In equal proportions with barley or rye, and a wheaten leaven 

 of one-fifth of the weight. Or still better with one entire half 

 of wheaten flour. 



Potatoes, 



In general the potatoe may serve when it is dry for one-half, 

 and wlien fresh or new for two-thirds, and even for four-fifths in 

 the fabrication of household bread. This last (luantity of four- 

 fifths is the greatest which the Commission has been able to 

 employ with advantage; but all their experiments with that 

 proportion have been attended vvith uniform success. 



Oats, barley, rice or maize, also mix well with potatoes, when 

 used with a wheaten leaven of one-fifth of the total weight. 



Employment of foreign Substances. 

 Various foreign substances have been recommended for am.e- 

 liorating the fabrication of bread, and correcting the faults of 

 damaged grain : such as the addition of alum, carbonate of soda, 

 magnesia, diluted sulphuric acid, salt of tartar, vinegar, sul- 

 phate of iron, gums, &;c. The Comniission have made experi- 

 ments with most of these suljstances ; and some of them do ap- 

 pear, in fact, to possess in a slight degree the qualities which 

 have been ascribed to them. But the Commission see no ne- 

 cessity for recurring to any such foreign aids, — most of which do 

 not in themselves possess any nutritive qualitv, — as long as bv a 

 previous desiccation of the grain, by good grinding and by pro- 

 per care, a wholesome bread may be obtained from a!l \Vet or 

 germinated grain, and as long as, even in the case of flour of the 

 most deteriorated description, it is only necessary to add a por- 

 tion of good flour to obtain an excellent household bread. 



XLIX. On Aerial Navigation. By A Correspondent. 



JLt is a singular circumstance in the history of the arts, that an 

 invention at its first appearance is frequently pursued with the 

 greatest eagerness, and yet will afterwards be wholly neglected 

 for years, until some happy improvement fixes it permanently on 

 the pul>lic attention. Many vvill remember the great zeal ex- 

 cited by the subject of aerial navigation, and the astonishing sub- 

 sequent neglect of an art so important, until the late revival of 

 the subject by Sir George Cayley and other eminent philoso- 

 phers. 



N 3 The 



