horse-power steam-engine from starting, with full pressure of steam on the piston, and no previous motion.  Not so, however, with this engine, for the breaking of the cord and contact with the battery occurred at the same instant of time, leaving an impression in the beam to the depth of the cord, despite the protection of the sole-leather.’  The engine continued to work in the most satisfactory manner; and Dr Page attached a circular-saw, which was used in wood, to a depth of six inches, and at a speed such as could be anticipated from the power which we afterwards found the engine to possess.

Careful experiments made to test the power of the engine, shewed it to be equal to seven horse nearly; and the estimate for consumption of acid and use of zinc is twenty cents for each horse-power per day of twenty-four hours.  The escape of acid vapours from the batteries is an evil that will have to be guarded against, to prevent the pernicious effects produced in several electro-plating establishments, where the health of the workmen has been seriously injured by the liberated gases.  This defect being overcome, Professor Page’s electro-magnetic engine may become highly valuable in engineering and manufacturing processes.  To quote the conclusions of the report—­’the cost will be less than that of a steam-engine of the same power:  the weight will be but one quarter, if boilers and contents be taken into account:  the expense of firemen and engineers is dispensed with:  buildings, and stocks of goods, and vessels may be more cheaply insured than when steam-engines are used, as there could be no risk from explosion or fire:  the expenses are only active while the machine is positively in action, whereas an ordinary steam-engine continues its expenses whenever the fire is burning.

’Dr Page’s engine, if used ten times during the day, of six minutes each time, would have but one hour’s expenses for the day; whereas a steam-engine, under similar circumstances, would be subject to nearly or quite the full expenses of fuel for twenty-four hours, or equal to the expenses of continuous work.’

THE SCIENCE OF COLOUR IN DRESS.

Unfortunately for our health and comfort, the teachings of science are too often disregarded, if they interfere with our habits.  Science, when not practically applied, loses its value; it wants fixedness, stability.  Its application is its embodiment; without it, it is a mere figment of the brain.  Its business is to inform the mind, and remove erroneous impressions; and its highest aim is usefulness.  The popular belief with respect to dress, that a black dress is warmer, both in winter and summer, than a white one, is erroneous.  The truth is that, the material being the same, a black dress is cool in winter and warm in summer—­while a white one is warm in winter and cool in summer; that is to say, the one is cool when we require warmth, and warm when we require to be cooled; while the other is warm when we are cool, and cool when we are warm, and thus answers the purpose of dress, which is, to protect the body from the influence of the weather.