SCIENTIFIC SUMMARY. 
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440 feet length, and 57 ft. beam, on which the railway cars could be run 
bodily, and which, from her great size, would be steady enough to obviate 
the danger of sea sickness. The engines proposed are oscillating engines of 
1500 collective horses’ power, and the passage between Dover and Calais 
would be made in one hour. 
Mechanics of Flight. — An extremely interesting paper on this subject was 
read by Mr. Wenham to the Aeronautical Society. The subject is too 
difficult and complex to be explained briefly, and therefore we will only say 
that Mr. Wenham has brought into the explanation of flight, the effect of 
the forward motion in retarding descent. Imagine a parallelogram 10 ft. 
long by 2 ft. broad, weighing 20 lbs. Such a body would descend in still 
air at the limiting rate of 1,320 ft. per minute, the resistance of the air 
put in motion by the plane balancing at that velocity the effect of gravity. 
If now a force be applied horizontally so as to carry the plane with its long 
side forwards at a speed of 30 miles per hour, then the motion of the plane 
being both downwards and forwards, a great volume of air will pass under 
the front margin of the plane, and will be carried downwards before leaving 
the hinder margin. The weight of air thus put in motion will be enormous, 
and the descending velocity of the plane proportionately reduced. Mr. 
Wenham calculates that the velocity of descent would in these circum- 
stances be reduced to of the passive rate of descent, or would not exceed 
83 ft. per minute. Each particle of air would then be moved downwards 
t 8 o of an inch by the passage of the plane, and conversely if this inclination 
were given to the plane it would move forwards without descending. Mr. 
Wenham finds that few birds can raise themselves vertically in the air, the 
exertion in that case being excessive. The eagle can only lift itself from 
the ground, by running with outstretched wings till its velocity having 
become sufficient, it glides into the air as if sliding on a frictionless plane. 
Electric Loom . — In one of the looms in the Paris Exhibition, electricity 
has been applied in a most ingenious manner to effect the immediate 
stoppage of the loom on the breakage of a thread, the emptying of a bobbin, 
or other trifling accident requiring the notice of the attendant. 
Type Writing Machine. — Mr. John Pratt, of Alabama, U. S., has recently 
brought out a machine for type writing, which was exhibited at the recent 
Soiree of the Institute of Civil Engineers, and which promises to be of 
much service. The writing is effected by pressing a series of keys like 
those of a piano-forte, which move into the necessary position a square 
frame carrying the type, and the letter is then impressed on the paper, by 
the stroke of a hammer, pressing the paper and an interposed carbonised 
sheet against the type. A document can be printed by the machine in about 
half the time necessary to write it in the ordinary way. Mr. Pratt thinks 
that if the machine comes into use it can be manufactured for three guineas, 
so simple and compact has it been made. A machine for stereotyping 
on a similar method, also the production of American ingenuity, is exhi- 
bited at Paris. 
Steel Armour Plates. — Renewed experiments have been made on steel as 
a material for armour-plating, and have been attended with more success 
than heretofore. The plates tested were 9 ft. by 4 ft. by 7 ins. They 
consisted of interposed laminae of iron and steel, and appeared to be welded 
