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JAXUARY 2, 1885.J THE PHOTOGRAPHIC NEWS. 13 loper. Another set was placed in a solation of potassium mono carbonate, and another in sodium mono-carbonate, and in these and the ammoniacal solution the gelatines were allowed to soak for one hour. The different kinds of gelatine were then placed without tension on glass plates, and again carefully measured. The following table shows the results obtained, the figures giving the linear expansion, taking the dried gelatine as unity Sodium or Potassium Water. Ammonia. Mono-carbonate. Nelson’s No. 1 ... 1-2 ... 139 1-29 Autotype 1-094 ... 1’28 ... 1-21 Heinrich’s 1-08 ... 1'22 ... 115 Simeon’s ... 1-05 ... 114 ... 1-09 Batty’s 132 ... 150 ... 1-42 X Opaque, Nelson’s 1-19 ... 1'40 ... 130 Cross & Blackwell’s 1'09 ... 1-21 ... 1-17 Amber 1-43 1-60 ... 1-51 The result of this table is somewhat curious. It shows that ammonia promotes frilling, whilst the mono-carbonates, though they cause a greater expansion than water alone, yet give a decidedly less inclination to frill than does the ammonia. This I have found in practice to be the case, so on this account, if on no other, the mono-carbonates are superior to ammonia in the deve loper. It is not hard cither, from this table, to pick out which are the soft and which the hard gelatines, the expansion being greater the softer the quality. The amount of water absorbed by some of these gelatines per 50 grains has already been published by me, and they are as follows:— a t. Water absorbed Ash per cent. per 50 grains. Nelson’s No. 1 Photographic 2 nearly ... 5} dr. Heinrich’s 2% „ ... 4 „ Simeon’s ... 2 ., ... 5 , Amber ... 10/, 4 Gelatine is altered if any quantity of ammonia is added to it, more pnrt’cularly when warm. As far as I can see, the tendency to frill is about the same as it is when it has not been so treated. There is no doubt that it is more sponge-like in its qualities— that is, much more permeable by the developer. Though deviating a little from the title of the paper, I wish to drawyour attention to an easy method of coating plates with gelatine emulsion, makng it flow like collodion. I have seen it stated that on Plates with a substratum of silicate it flows well. My own experience is the reverse. I have found that, as a rule, with silicate and albumen the emulsion drags excessively, as it does with silicate alone. There have been cases in which the plates have, flowed well, but that was quite an exception. (I would put in a parenthesis that there is no necessity to wash the substratum after it has been applied. I did so at first, but have found it needless, the slight excess of potash or soda having no appreciable effect nn development. I have once or twice thought that- it promoted a little blue fog at the back of the film, but I don’t think it is the case.) Gelatine substratum I have found always drag most tremendously. A little dodge gets over all this difficulty. A piece of swandown calico is wrapped round a squeegee and slightly damped. Just before coating the plate, the muffled squeegee is drawn a couple of times over the surface to be coated, and the emulsion immediately flowed over. It will be found to run evenly and rapidly. With a plate-coating machine of course this dodge is unnecessary. A SCAMPER ACROSS A CONTINENT WITH A CAMERA. Being a continuation of “ With the British Association.’’* BY R. O. BROOK. In continuation of my paper given at our last meeting, you will remember that I left you at the entrance of Lake Superior. During our sail up the lake, the day was very gloomy, especi ally so as wo passed Silver Island and Thunder Cape. The latter is a basaltic cliff, 1,350 feet high, on whose summit is the crater of an extinct volcano. I should have exposed a plate or two here and at Port Arthur, but the weather was unfavour- 2 leit being stormy and gloomy, with rain falling all the time. nd not a favourable opportunity of exposing another plate U i we reached the Rocky Mountains at Kicking-IIorse Pass, • Page 828, last volume. the present (September 13th, 1884) terminus of the Canadian and Pacific Railway. I may mention here a circumstance that occurred during the journey from Port Arthur. We arrived at V'innipeg at four o’clock a.m., at which time we were all abed, of course. Pre vious to having my berth made up, I had taken out of my Glad stone bag what I required at the time, and passed the bag, along with my stick, umbrella, and camera stand, into the next car, to give more room in my berth. I had been given to understand that this train was a special one for the members of the British Association, so never thought for a moment that any cars were going to he taken away ; but, on arriving at Winnipeg, the car containing my baggage mentioned had quietly been taken off, and my things had gone off, much to my disgust and annoyance, as my ruby lamp was in the bag, and how I was to manage with out my camera stand I was at a loss to know. However, on arriving at Kicking-Horse Pass, and having my attention directed to a pretty waterfall in the forest, on the mountain side, I exposed one plate, steadying my camera on a rail. This view was taken on the plate I had exposed at Sault Marie Rapids, as, after travelling so far, I had forgotten having previously exposed this particular plate—the fault of trusting too much to one’s memory. The mistake was unfortunate, as, from the appearance of the negative, both views would have been good. I could not ascertain that these falls were known by any name, so I named them the “ Kicking-Horse Falls,” as their descending waters flow into Kicking-Horse Lake, and thence to the Pacific Ocean. It may interest you to know that this Pass is so called from an accident that happened to Dr. Cheadle, by his horse kicking here when he was crossing “ The Rockies" some twenty years ago. The variety of scenery here about, puzzled me how to dispose of my plates to the best advantage. One could readily use a few dozen plates in this wildly-romantic locality without ex hausting the views, whereas I had only three double slides, and could not see any facilities for changing here. I next took a view of the Lake, and the snow-capped moun tains beyond, which I managed by placing my camera on the stump of a tree. The railway is being constructed from here to the Pacific, and a construction train, consisting of a number of trucks, carrying workmen and materials, was about to go down the line some eight miles, so I got upon one of the trucks to see what I might. The train moved very slowly, and stopped frequently, as the line was very steep and exceedingly rough. During stoppages I had opportunities of exposing two plates, placing my camera upon a box of bolts that was on the truck. As we were about entering a short tunnel, a messenger stopped the train, saying that an accident had just occurred immediately beyond the tunnel, which is a short one, through a portion of a mountain that could not conveniently be rounded. At the other side of this moun tain lies a deep ravine, which was crossed by a strong wooden bridge, over which the train had to pass, and upon this bridge a large mass of rock had fallen, breaking it down, and bending the rails up like wire. Two or three of our party, who had gone on before, narrowly escaped destruction, as, just as they were about to step on the bridge, the mighty mass of rock camo crashing down, and ono gentleman went part way down with a portion of the wreck, providentially escaping with a few bruises, but with no slight shock. I took a view of this tunnel from the side of the land slip, placing my camera upon the end of a piece of sleeper that lay there handy, and then scrambled over the broken bridge to take one of it. My camera was fixed in only a very rickety position, and on turning to get a slide out of my case the wind carried my camera down the steep embankment; but luckily it was stopped before getting as far as the river below, a depth of some hundreds of feet, by a bush; a lucky circumstance, as, had its downward course not been arrested so, I should have had but little chance of ever recovering it. When I did get it again the ground glass was broken to bits, and some of the brass work was broken off, so this climax put a period to photographing at that time ; therefore I commenced to return, enjoying the scenery and the walk back, though it was tough, up-hillwork, a distance of eight miles, over wild, rugged land. This place is in British Columbia, 5,500 feet above the sea level, 120° west, and standing here I reflected that I had tra versed one-third of the entire globe. The wild and majestic grandeur of the scenery here about made me forget my burden, though on arriving back at Kicking-Horse Pass I was “ dead