170 REPORT—1863. 
Rouen, the Rue Lafayette, the new streets and boulevards on the island of the 
Cité, and the left bank of the Seine, must have entailed a very considerable ex- 
pense for levelling the ground, and the works that are required to make the ap- 
proaches. The same principle has also been adopted in them as in the parts 
already undertaken; and the quantity of land abandoned for the use of the public 
was very large. Mr. Tite also incidentally alluded to the outlay that the town 
had incurred in the laying out of the Bois de Boulogne, the Pare Monceaux, the 
Bois de Vincennes, the squares of St. Jacques la Boucherie, the Place du Con- 
servatoire, the Palais des Thermes, which he admired very much, but which he 
considered it would be impossible to execute with a municipal body elected by the 
people who paid for them. 
. Tite stated that he had applied, through Parliament, for the statistics of the 
improvements of the city of London, but he had not succeeded in obtaining them ; 
all that he had been able to learn was, that the New Cannon Street had cost £589,470, 
or about £506 per yard forward, and the New Victoria Street £330,675, or about 
£300 per yard forward; but he had not been able to ascertain what the City had 
derived from the sale of the land, old materials, &c., in either case. He, however, 
stated that his experience in this matter was, that the expense attending the con- 
version of inhabited house-rent to ground-rents was always an operation that was 
costly in its nature, whatever improvement might be made in the character of 
the houses; and he was disposed to consider the loss of this operation, which 
must always be incurred when town improvements are undertaken, was about 70 per 
cent. of the outlay. The results of the operations in Paris only confirmed him 
in this opinion. 
Mr. Tite finished his paper by calling attention to the means that the city of Paris 
adopted to meet the calls that were thus made upon it, and for the current expenses 
of the town. He showed that the ordinary budget of the town was 112,536,778-08 
franes, of which the Octroi duties constituted the major part, they being 83,325,816 
francs; the extraordinary budget brought this total to 119,935,272-91 frances, and 
the supplementary receipts, including the proceeds of the loan, swelled the total 
sum to 199,807,203-20 francs. From this he concluded that great caution ought to 
be observed in increasing the debt of Paris, which already had to provide the sum 
of 10,546,788°64 francs for the interest of that debt. 
Mr. Tite, in conclusion, warmly acknowledged his obligations to His Excellency 
Lord Cowley and the Prefect of the Seine, Baron Haussman, for the valuable 
documents which had enabled him to prepare this paper. 
MECHANICAL SCIENCE. 
On an Improved Caisson Gate. By Admiral Sir Epwarp BrrcHer. 
Tue floating dock-gates proposed were constructed similar to caissons now used 
in the royal yards, but in this instance in pairs hinged at the apex, thus facili- 
tating the insertion of the bearing ends into the abutting cavities. They thus 
‘orm together a complete arch, more effectual the greater the resistance or external 
pressure may be against the ingress of water. In undocking, those caissons could 
be attached under the counter cf a vessel, and act as a lift, should there be any 
want of water to float her out. 
A brief Description of a Spirit-level Telescope for observing Altitudes and 
obtaining Latitudes independently of natural or artificial Horizons. By 
Admiral Sir Epwarp Betcuer. 
The telescope is fitted similarly to the transit telescope, with an oblique dia- 
phragm for illuminating the wires. But in this instrument, which has no Y sup- 
ports, or axis for illumination, the light is reflected through a slit in the upper 
side, which carries a transparent level tube. The bubble brought into contact with 
