Let's look into the matter of fixing baths and the chemical action that takes place in fixing a plate or print, and see how important the fixing bath really is.

Proper fixing removes all the sensitive silver salt which has not been acted upon by light or the developer. We will consider the fixing of both plates and paper in order to make ourselves perfectly clear.

The fixing bath has two functions. The first is the formation of a double salt of sodium hyposulphite and silver bromide, at which point a negative is clear and apparently fixed. The double salt so formed is insoluble in water and cannot be removed by washing. It cannot be seen and the negative appears to be fixed, and just here lies the danger, for if the negative is washed and dried, this double salt will turn yellow on exposure to light, and in time the image will fade more or less. Of course, practically the same thing occurs in fixing a print, though the clearing cannot be seen as in the negative.

The second function of the fixing bath is the dissolving away of the double salt first formed. Although insoluble in water, a longer soaking in the fixing bath will convert the first double salt into a second double salt which water will dissolve and readily wash from the film.

From An Artura Iris Print.

From An Artura Iris Print. By O. C. Conkling St. Louis, Mo.

You can readily see why you are advised to allow plates to remain in the fixing bath for some time after they appear to be perfectly clear and why you have stained negatives when you do not.

However, improper fixing is not the cause for all stains on negatives and prints. If the developer is not properly rinsed from negatives or prints before they are placed in the fixing bath, they are very readily stained. Using the same fixing bath for several different developers will often cause stains if a quantity of these developers is carried into the fixing bath.

The most common cause for stains, however, is the use of a weak or over-worked fixing bath. In either case there may be enough hypo in the bath to form the first double salt, but as it requires an excess of hypo to form the second salt, which is soluble in water, the second function of the fixing bath is not performed, even though the negative may be clear or the print have remained in the bath for the proper length of time. Stained negatives and prints are the result, and both will deteriorate or fade in time.

Another mistake is to make the fixing bath too strong. It may seem strange to you, but a plate will fix properly in a 25 per cent. solution of hypo quicker than in a 50 per cent. solution, while prints require a still weaker solution for best results.

When these facts have been gone over carefully, you will readily see the importance of fresh fixing baths if you would be sure of your results. And you will better understand the desire of the manufacturer and demonstrator to help you secure better results.

Listen to the demonstrator's or manufacturer's advice and ask "why" as often as you like, for there is a reason for all things.

December. Our Illustrations

You can't help admiring a man with steadfastness of purpose who begins at the bottom, follows the line of work he likes best and keeps climbing until he has reached a position in his chosen profession where it may be said of him:- there is a successful business man.

And if the particular task he has chosen is one of the most difficult and arduous - one that others would often prefer to evade, so much greater is the credit due him.

Mr. Conkling of St. Louis, Mo., photographer of children, entered business for himself thirteen years ago, after having served his apprenticeship under Guerin, generally admitted to No. 3. The purpose of this solution is to neutralize the Fluoride, as without doing this, permanent contact with another plate could not be secured. Three minutes in Solution No. 3 is sufficient. Then lift as before and transfer to a larger tray containing clear water and a plate, preferably of a little larger size, which has been fixed and thoroughly washed but not developed. This gives a gelatine coated plate which is perfectly clear and transparent. Float the loose film onto the gelatine side of the new plate, lift out of the water and squeegee with a wet blotter to remove air bubbles, then set up to dry. The use of a larger plate for transfer is desirable, as it is a convenience in placing and handling the film. If properly hardened in Solution No. 1, the film will not stretch to any perceptible extent in the process of transferring.

From An Artura Iris Print By O. C. Conkling St. Louis, Mo.

From An Artura Iris Print By O. C. Conkling St. Louis, Mo.

If a negative has been retouched or varnished, it would, of course, be necessary to remove the retouching dope or varnish before treating in the several solutions. Alcohol or turpentine should be used for this purpose.