This rendered it necessary to give up the idea of using a belt, since it was not possible to prevent its getting wet.  Cords could not be found in the country, and so it was necessary to make use of a too heavy chain, which was in no wise intended for such a purpose, and which at a velocity of 15 revolutions began to swing and necessarily absorbed much power.  The large pulley drove one of 0.4 m. upon an intermediate shaft.  Upon this latter a 2.6 m. wooden pulley directly drove, through a belt, the 0.2 m. pulley of the generatrix.

From this may be judged what the country’s resources are.  The motor, by means of a belt, actuated a windlass provided with suitable checking gearings.  The distance of the two machines was 116 meters.  Save the transmission by chain, the whole worked in a satisfactory manner.  The performance could only be estimated in a lump, by comparing on the one hand the theoretical work of the fall of water, and, on the other, that of the vertical elevation of the car; and, further, one was obliged to estimate the weight of the latter.  If we allow 1,000 kilogrammes for the weight of a car that received 360 liters of dry sand or 300 of wet, the performance was 19 per cent., and appeared to be satisfactory, considering the conditions under which the installation was made.  This experiment was at all events of such a nature as to indicate the use of these machines in cases where the arrangement of the locality absolutely necessitates a transmission of power.

The first workmen reached Portao de Ferro December 15, 1882, and the material shipped from France did not arrive until April 25, 1883.  Operations were suspended about the 25th of September, since, for a fortnight already, there had no longer been any doubt as to the manner in which the river bed had been cleaned by former operators.

As a result of this first experiment, the proof remained that it would be easy in future exploitations to introduce into the country methods of work that are quicker and more economical than those now in use.  In fact, all the operations were performed with natives of the country, with the exception of a carpenter and blacksmith from Rio Janeiro.—­La Nature.

* * * * *

WHAT WE REALLY KNOW ABOUT ASIATIC CHOLERA.

NEW YORK, September 1, 1884.

To the Editor of the New York Medical Journal: 

SIR:  I have been exceedingly interested in Dr. Bartlett’s suggestive article in your issue of August 30.  But a sufficient number of well-established facts are known to account for all the peculiarities and vagaries of cholera.

1.  Cholera has existed in Hindostan for centuries.  It was found there by Vasco da Gama in 1496, and there is a perfectly authentic history of it from that time down to the present.