On the Orbiis of ihe newly discovered Planets. 131 
for the valves. I believe that I have succeeded in doing 
what I wished, and that the valve which I have invented 
for the purpose will render it possible to erect engmes of 
this sort for large streams of water, and consequently with 
eylinders of large diameters, which may act as well as those 
formerly erected have done with smali streams applied with 
considerable falls. 
I have as high a respect for the talents of Mr. Trevithick 
as Mr, Farey can have, and admire the ingenuity displayed 
by him in the construction of bis pressure engines, as well 
asin other instances. I believe that the merit of bringing 
this kind of engine to a considerable degree of perfection 
may be ascribed to him: but { apprehend he only recom- 
mended them in cases where a small stream might be ap- 
plied with a considerable fall. 
It may, bowever, often occur in certain situations, that 
it should: be desirable to apply a copious stream where the 
fall may be greater than any overshot wheel can well be 
built for, or “where wheels cannot conveniently be placed : 
In such circumstances I think my engine would be a useful 
one. 
I shall, however, speak with more confidence on the sub- 
ject whe its merits shall have been more fully tried. Per- 
haps I imay at a fulure time trouble you with some re- 
marks on the action of this engine, and then Mr. Farey 
will have an opportunity of comparing it with those which 
he has seen. 
I am, sir, 
Your most obedient servant, 
Holwell, near Tavistock, - J. TAYLOR. 
Feb. 5, 1811. 
XXV. Onthe Orlits of the newly discovered Planets. By 
Mr. Firmincenr, late Assistant at the Royal Qhsangetegy 
Greenwich. 
Brice the discovery of the four smal] platiets Ceres, Pallas, 
Vesta, arid Juno, little seems to have been known in this 
country respecting their situations, The astronomers on 
the ‘continent, however, have been more successful, and 
have not only kept up a constant series of observations on 
these small bodies, bit have, with that indefatigable labour 
and address in the application of mathematics to every de- 
partment of science, for which they are so peculiarly emi- 
nent, availed themselycs of every opportunity to impraus 
the 
v 
