T H E J O U R X A L OF IiVDliSTRIAL A N D ENGIYEERING C H E M I S T P Y
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have a slight lever movement about t h e point where it passes through t h e rubber stopper D: as a fulcrum. The rubber stopper D is cut very short a n d , t o give t h e t u b e E still greater freedom of movement. t h e hole cut for it m a y have t h e edges grooved on both sides. The “ Y ” on t h e end of E should be constructed with a rather small branch (about z mm.) as t h e extension of E , while t h e branch looking down should have t h e full opening of E (6 mm.). When B is depressed t h e small branch of t h e . i Y ’ ’ should be raised just above t h e surface of t h e mercury t h a t fills t h e lower end of C, t h e larger branch of t h e “ Y ” remaining below t h e surface. K h e n B rises slightly, both
FIG.I
-a
A-Round, narrow-mouthed, 1 lb. bottle with the bottom cut off. B-4 02. oil sample-bottle with the bottom cut off. C-25 mrn. X 20 crn. test-tube. E-6 mm. glass tube bent and provided with “Y” a t the end.
openings of t h e “ Y ” will submerge in t h e mercury. With t h e assembly made as described, A is filled about full of mineral oil a n d t h e apparatus is ready for use. Gas flows into C through t h e t u b e connection shown, from there through E t o B and out through t h e t u b e from A . As soon as t h e pressure builds u p sufficiently on t h e delivery side t h e bell B floats u p slightly, plunging t h e end of E below t h e mercury and shutting off t h e gas till consumption again slightly reduces t h e pressure under B . As t h e end of E rises from t h e mercury t h e slug of mercury t h a t has closed t h e small branch of t h e “Y” is forced up into E , b u t is permitted t o flow back through t h e lower branch of t h e ((Y.’. T h e gas pressure on t h e delivery side can be regulated b y t h e weight of B or t h e length of E . Once set up a n d adjusted, this siniple apparatus will automatically deliver gas a t a reduced b u t constant pressure, irrespective of variations of t h e initial pressure. ARXOURGLUEWORKS,CHICAGO
A NEW FORM OF ABSORPTION BOTTLE FOR USE WITH EITHER CALCIUM CHLORIDE OR SODA LIME IN THE ELEMENTAL ANALYSIS OF CARBON AND HYDROGEN IN ORGANIC SUBSTANCES1 By HARRYI,. FISHER Received February 29. 1916
The U-tube as a container of calcium chloride or soda lime for t h e absorption of water a n d of carbon dioxide, respectively. has been in use for many years. I n general it is efficient, b u t on account of its shape i t has many disadvantages in t h a t it is fragile a n d u n wieldly, a n d presents difficulties of support during 1 Presented a t the Seattle Meeting of the American Chemical Society, September, 1915.
Vol. 8, No. 4
t h e combustion and weighing a n d of filling a n d emptying which do not make it very popular, especially with students. The addition of ground-in stoppers, a n d of a brace a n d support for hanging as suggested b y &IcIntire,l were very acceptable improvements. The tendency, however, has been t o use a bottle form of apparatus because this is easier t o handle iri every way. This new style of absorption bottle has a n inner t u b e fused t o t h e bottom of t h e bottle and a single, hollow, ground-in stopper which makes a gas-tight joint i n t h e neck of t h e bottle a n d t h e t o p of t h e inner t u b e . Two kinds of stoppers have been designed as shown in t h e accompanying diagrams. In Pig. I , opposite t h e hole in t h e hollow stopper there is a narrow longitudinal depression about z mm. deep a n d 3 mm. wide. This is t o allow communication with t h e outer chamber a n d t h e side tube a t t h e same time t h a t t h e inner chamber IS in communication with t h e other side tube b y means of t h e hole in t h e stopper. When t h e stopper is turned, communication is then entirely s h u t off from both tubes a t t h e same time. Around the bottom of t h e inner t u b e there are four small holes. T h e two arms or side tubes are bent upwards slightly where joined t o the
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neck in order t h a t in t h e collection of moisture a n y droplets t h a t may remain i n t h e a r m will not easily run out when t h e apparatus is being disconnected. One a r m is provided with a small ground-in stopper t o prevent loss of moisture when t h e bottle is not connected in t h e absorption train. Only a minimum amount of grease should be used on this stopper so as not t o introduce any chance of loss with consequent error in weighing. The upper edge of t h e neck is beveled a n d smooth t o allow thorough cleaning. T h e bottle has a total available capacity of 3 0 cc., 6 cc. for t h e inner chamber a n d 2 4 cc. for t h e outer chamber. By way of comparison an ordinary 11 cm. U-tube has a n available capacity of z z cc. A larger stopper cannot advantageously be made because of t h e difficulty of drawing it out a n d lining it u p for t h e grinding. T h e bottle represented in Fig. I1 has a small curved tube in t h e stopper which connects t h e opening in one a r m with t h e large inner t u b e of t h e bottle. The gas passes tlirough t h e inner tube as in t h e other bottle 1
J . A m e v , Chsm. Sor,, 33 (1911). 450-1.
Apr., 1916
T H E JOCRLVdL OF I N D U S T R I A L A N D ENGINEERING C H E M I S T R Y
a n d i n t o t h e outer chamber through t h e small holes at t h e b o t t o m a n d t h e n into t h e inside of t h e stopper through t h e two holes a n d on into t h e opposite arm. XOTES
wATER-calcium chloride is used a n d t h e gas passed through t h e inner t u b e first. The small a m o u n t of calcium chloride in t h e inner tube becomes exhausted first a n d can be replaced a t a n y time, whereas t h e larger a m o u n t in t h e outer chamber will last for many combustions. By greasing t h e inside of t h e inner t u b e , t h e caked calcium chloride will not stick t o t h e walls, and can easily be removed. When filled, t h e bottle weighs approximately j j g. F O R C A R B O N DIOXIDE-The inner t u b e is filled with calcium chloride or small pieces of solid potassium hydroxide, a n d t h e outer chamber with moist soda lime. T h e gas is passed through t h e outer chamber first. When t h e bottle is filled in this manner a n extra weighed guard bottle containing soda lime a n d calcium chloride is not necessary although it is recommended for careful work since i t gives a n indication of t h e efficiency of t h e absorption. When filled, t h e bottle weighs about 6 j g. FILLmG-The inner t u b e is filled first, a plug of cotton or glass wool being p u t a t the bottom t o protect t h e holes, a n d t h e absorbing reagent covered with another plug of cotton or glass wool. A loose plug of cotton is t h e n p u t on t o p t o a c t as a cap while t h e outer chamber is being filled a n d then removed, leaving t h e ground surface clean a n d ready for greasing. T h e ground joint in t h e inner t u b e should be well greased, because if this joint becomes “frozen,” there is no opportunity of getting a t it b y t h e usual methods. A piece of copper wire a n d a pair of narrow forceps are a great help in filling a n d emptying t h e bottle. I n order t o prove t h a t t h e ground joints of t h e a p p a r a t u s are @+tight, before using, a d d some water, FOR
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a n d while passing air through t h e inner tube, close t h e stopper. T h e liquid should remain a t its high level. When inserting t h e stlopper, i t is well t o see t h a t t h e holes are coincident in order t o avoid a n y excess of pressure in t h e bottle. ADVANTAGES
I-The apparatus can be easily a n d thoroughly cleaned. 2-It has only one hollow stopper and one turn of this s h u t s off both openings. 3-It will s t a n d upon t h e balance pan a n d needs no hangers when joined in t h e absorption train. 4-It makes no difference which way t h e bottle is connected up, since t h e course of t h e gas is controlled b y t h e single stopper. I n t h e determination of moist u r e , i t is of course advisable t o pass t h e gas through t h e a r m fitted with t h e small ground-in stopper. ;-It is provided with a small stopper as recommended b y Dennstedt t o prevent loss of a n y moisture remaining in t h e arm. 6-The arms are bent upward at t h e neck in order t o prevent in a measure a n y droplets of water which may remain from being lost when t h e bottle is being disconnected. 7-The upper edge of t h e neck is beveled a n d smooth so t h a t t h e excess of grease can be easily removed. T h e bottle shown in Fig. I is of more general use because i t hgs a wide stopper which is open a n d can be easily cleaned. The stopper of t h e bottle repyesented b y Fig. I1 is more difficult t o clean b u t was designed with t h e idea of catching t h e condensation liquid i n a drip cup. Both forms of absorption bottles have been in use for almost a year. They were made b y Emil Greiner a n d Co., New York. LABORATORY OF ORGANIC CHEMISTRY COLUMBIA UNIVERSITY, NEW YORKCITY
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ADDRESSES THE SEATTLE WATER SUPPLY’ By JOHN WEINZIRL
Like the water supply of any large city, the Seattle supply has had an interesting evolutionary history; much of this history is not essentially different from that of other supplies, but parts of it are quite unique if the writer is correctly informed. This paper will sketch the history in outline only, give the present status of the supply, dwell upon the unique features, and draw one or two conclusions. In the early days when Seattle occupied one or two streets along the water front, the numerous springs from the hills furnished the water supply. -4s these sources became dangerous or inadequate, pumping from Lake Washington was begun; this supply served for 20 years, or until 1900. The pumping was regarded as expensive and the plant installed was not adequate for fire protection, as the great fire of 1887 demonstrated. It was apparent, too, that the Lake would be polluted in time, and that either the supply would have to be purified or a new one found. In 1890 the latter plan was adopted, Address before the Water, Sewage and Sanitation Section a t the S l s t Meeting of the American Chemical Society, Seattle, -4ugust 31 to September 3, 1915.
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and I O years were spent in putting the present Cedar River supply in operation. In making the change from the lake supply to the mountain supply, private ownership gave way to public ownership, and with it prices have fallen to approximately one-third the former cost. At the present time $0.50 per month is the minimum rate for homes with meters, and the cost exceeds this rate only when irrigation or some other cause increases the consumption. With respect to this phase, and all the engineering and economic problems involved, the city has published a most valuable and interesting book entitled “The Seattle Municipal Water Plant;” it furnishes a wealth of detail to those interested in this aspect of the water problem. CEDAR RIVER SUPPLY
Cedar River drains an area of approximately 156 sq. mi. in the Cascade Mountains. Most of the area is covered with primeval forest, and the soil is largely glacial drift. The intake of the gravity system is a t Landsburg, 28.57 mi. from Seattle, and two pipe lines carry the supply. From Landsburg to Cedar Falls where the municipal power plant is located, the Milwaukee Railroad follows the river in close proximity for 1 2 mi. Midway a t Barnston, on the left bank of the river is a logging camp
