the ANALYST'S column L. T. Hallett, Editor
WELCH ELECTRIC LABORATORY STIRRER with gfzatÂUu
INDUCTION TYPE MOTOR
Speed Controlled—Long Wearing —Non-Sparking
A
T EVERY meeting of a technical or
professional society, papers presented run the whole gamut in effectiveness. Since the technical quality of papers presented at ACS meetings, for example, is high, the effectiveness is based largely on the presentation. This concept is described in an informal pamphlet, "Techniques for Better Talks at Wescon," prepared for speakers at the recent Western Electronic Show and Convention. Authors are members of the Los Angeles Professional Group on Engineering Writing and Speech of the Institute of liadio Engineers. The guide emphasizes that the speaker has an obligation to his audience, himself, and the sponsoring society to communicate his ideas intelligibly. A scientist who has the technical competence and initiative to prepare an acceptable paper, has the ability to make an effective oral presentation. All that he needs is to take time to develop his talk. In doing so he should keep a few facts in mind: 1. The listener saturates far more readily than the speaker. For the audience to hear with comprehension, the speaker must time and pace his talk carefully, use short sentences, talk slowly in a conversational manner, and pause lor digestion of facts, particularly after presenting difficult concepts. 2. A talk is not a paper. To hold his audience, the speaker should not read the paper or commit it to memory. Ile should discuss essential features, including a brief outline of the subject, reasons for the work, chronology, accomplishments, and actual and possible applications. Mention of further work needed will help stimulate questions front the audience in the discussion period. The speaker should commit the essential features to memory by writing them down, taping them on a recorder, and discussing them with associates, lie is then ready to talk to his audience. o. Timing. A 20-minute oral presentation will consist of 2500 to 3000 words or approximately 10 double-spaced
Reduces Explosion Hazard Watt-Type
Governor
Stabilizes
Speed'
Delicately Controlled Variable Range of Speed ( 2 0 0 to 1 , 4 0 0 R.P.M.)
$54.75
Long Life and Dependable Service No.
5230. ELECTRIC STIRRER, Sparkless. Complete with 6-foot connecting cord, line switch, and plug. For operation on 50 or 60 cycles, 115 volts A.C. Each $54.75
5230
5230A. ELECTRIC STIRRER, Sparkless, for 230 Volts, A.C. Consists of No. 2530 Stirrer equipped with a step-down transformer to permit operation on 2IÎ0 volts 50 or 60 cycles A.C. Each $64.50
W . M . WELCH SCIENTIFIC
COMPANY
DIVISION OF WELCH MANUFACTURING COMPANY
*
ESTABLISHED 1 8 8 0 1515 SEDGWICK STREET, DEPT. A - 1 , C H I C A G O 10, ILLINOIS, U.S.A. Manufacturers of Scientific Instruments and Laboratory Apparatus
H E V I - D U T Y "Multiple Unit" TUBE TYPE COMBUSTION FURNACES in Two Temperature Ranges, 1850° F. or 2200° F. Hevi-Duty Combustion Tube Furnaces are available in either the split* (illustrated) or solid type and can be used horizontally or modified for vertical operation. Long-life "Multiple Unit" brand heating units offer fast heat-up because the heat is radiated directly into the heating chamber. The heated length may be divided for zone t e m p e r a t u r e control which gives greater temperature uniformity over a specified length. A few of the standard furnaces are shown below. M a n y sizes are in stock. Special sizes with diameters up to 16 inches can be built t o your specifications. ,;; 5-in. and smaller diameters are hinged.
HINGED-TYPE TUBE FURNACE FOR 1 8 5 0 ° F. TYPE
CHAMBER DIA.
LENGTH
RATING WATTS
SHIPPING WEIGHT
PRICE
70
l'A"
12"
750
35
$
75.00
M-2012
2%" 3"
12"
1400
90
$
165.00
24"
3400
135
S 250.00
5"
36"
7500
325
$
8"
40"
14500
520
S1180.00
M-3024 M-5036 M-8040
• LABORATORY
HEVI DUTY
ELECTRIC CO. Milwaukee ),,Wisconsin
Write for Bulletin 552 for complete details.
650.00
FURNACES TRADE
MULTIPLE UNIT MARK
• ELECTRIC
EXCLUSIVE
For further information, circle number 63 A on Readers' Service Card, page 101 A VOL. 3 0 , N O . 1 0 , OCTOBER 1 9 5 8 ·
6 3 A
