242 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
districts. Whether they repay the owner is another matter, seeing how 
much they consume. 
An abundant source of manure is afforded also by the ruins of ancient 
towns, which were built of unbaked clay, but now consist of mounds of 
earth recognisable only as masses of ruins by the fragments of pottery 
they contain. Out of these mounds, which contain the rubbish of 
thousands of years, is dug a kind of earth known as sebbakh," some- 
times containing as much as 12 per cent, of saltpetre, soda, ammonia, 
and other salts. 
One meets continually string after string of camels, which have con- 
veyed produce into Cairo, returning laden with this manure, all carried 
in paniers, and the same thing is frequently observed all along the Nile 
banks. 
Tools. — Those used are most primitive, consisting only of the plough 
and a kind of mattock or hoe. 
The plough is exactly similar to that used thousands of years ago, as 
can be seen by the hieroglyphics in the tombs and elsewhere. It merely 
scratches the surface of the ground, being held by one hand whilst the 
other holds the goad, which is used freely but not unkindly. 
In conclusion, I may say we saw no Papyrus growing wild, and we 
were informed it was to be found now only above Khartum. It is this 
which was recently cut through in that part of the river to allow of 
water communication with Fashoda and the districts beyond Khartum 
being renewed. 
Nor are there any rushes growing now at the spot where Moses is 
said to have been hidden by his parents. 
That the country has very much changed since that time none will be 
surprised to hear, and nothing proves this more than the petrified forests 
which are to be seen not far from Cairo. We visited one of these, and 
saw the remains of many trees. Whether these grew there originally or 
were floated thither is unknown. Certain it is that no living trees are now 
to be seen anywhere near the spot we visited, and so far as can be ascer- 
tained none corresponding to these petrified remains are now to be found. 
These trees do not appear to have been Palms. 
