In the case of composite colour, an infinity of systems must be obtained for maxima infinitely slight and with an infinity of interval values separat….

[On the Gaussian curve, remarked to Poincaré:] Experimentalists think that it is a mathematical theorem while the mathematicians believe it to be an ….

Most of these pictures, taken while travelling, were developed on the mantelpiece of a hotel room, which proves that the method is easy enough to car….

Life is short and progress is slow.

I got quite good results from protein plates..

The problem of direct colour photography has been facing us since the turn of the last century..

When the shot is afterwards subjected to white light, colour appears because of selective reflection..

The series of photographic operations, developing, washing, final drying, takes about quarter of an hour..