SCIENTIFIC SUMMARY. 
473 
Petroleum for Steam Engines. — Some experiments have been lately made 
in America which seem to show that petroleum has many advantages as a 
fuel oyer coal. A gunboat called the Palos was used for the experiments. 
She had been built for the Government, to make a speed of eight knots an 
hour, and with coal could never be forced beyond that. First she was tied 
to the dock, and the possibility of getting-up steam with petroleum was 
demonstrated. She was then sent on a trial trip down the harbour. Steam 
was got up with petroleum in 25 minutes, and the Palos steamed down the 
harbour and back, a distance of 25 nautical miles, in 1 hour and 55 minutes. 
In making this trip she consumed but four barrels of petroleum. The fires 
are reported to be kindled and extinguished with nearly the same ease as 
lighting and extinguishing a gas-burner. The furnaces of the Palos, 
originally built for burning coal, were fitted at comparatively small expense 
with burners, to which the petroleum was led by pipes from the tanks on 
deck. The burners, by their own heat, turn the petroleum in the pipes into 
gas, and in this form it is burnt. The flames produced are intensely hot, 
and the petroleum burnt on the trip produced as much steam as 20 times its 
bulk in coals — a great saving of room in ocean voyages. The dangerous 
properties of the petroleum appear to be the only drawback to its use in this 
way, for coal-burning furnaces can be adapted to its use at but a trifling- 
expense. The supply of petroleum is now so much greater than the demand 
that, even with three-fourths of the wells in the producing regions aban- 
doned, it can be bought for 2d. a gallon. Its cheapness is, therefore, another 
strong inducement to use it for generating steam. 
Anticrustation Mixture for Boilers. — The following recipe is given in a 
number of Eisner's chemisch-technische Notizen: — 125 kilos, of crystallised 
chloride of barium dissolved in 50 kilos, of water with addition of 25 kilos, 
of hydrochloric acid (specific gravity T20). To every 1000 litres = 1 cubic 
metre = 35 -5 cubic feet English, 15 litres of this acid solution should be 
applied. 
Constitution of Fire-Clays. — In a paper published in a late number of 
Silliman's Journal , Messrs. Johnson and Blake state that compounds, such as 
pipe-clay, fire-clay, and kaolin, all contain a peculiar crystalline substance, 
which they term kaolinite. Seen under the microscope by reflected light 
these clays appear white, but when the light is sent through them they appear 
translucent. Interspersed among the particles may be seen curiously plate- 
shaped particles 0*0001 of an inch in breadth. 
Blast Furnace. — It is stated in the Bevue Universelle that Morgan’s method 
of increasing the production of ^blast-furnaces sixfold, is by giving them 
greater dimensions, for instance, 9| metres in diameter, blowing into the 
furnace by 12 tuyeres. A hollow cone is besides constructed in the middle 
part of the bottom of the furnace, by means of which a blast is also intro- 
duced into the furnace. 
Artificial Gold. — The alloy bearing this name has recently attracted some 
attention in this country from the supposition that its employment is likely 
to benefit on tin and copper workers. A contemporary gives the following 
account of it : — It is composed of pure copper, 100 parts; pure tin, 17 
parts ; magnesia, 6 parts ; tartar of commerce, 9 parts ; sal ammoniac, 
3-6 parts ; and quicklime, T6 part. The copper is first melted, then the 
