LABORATORY SPACEfor CHEMICAL MICROSCOPY' CARL E. OTTO University of Maine, Orono, Maine
Many instructors who see the advantages of chemical The ordinary chemical laboratory tables are unsuited for microscofi cunnot find a suitable s@ce in their crowded this work for the student cannot sit or stand in front of buildings for this type of laboratory. The purpose of this them in a comfortable position and look through a microarticle is to show how this problem was solved in one in- scope. After considering all possible locations a ihreestance and to suggest like possibilities to other teachers. foot st* across the rear of a recitation room was selected and desks were designed combining comfort for the student 'Presented before the Division of Microchemistry at the ninety-eighth meeting of the A. C. s., B O S ~ O ~M,-., september with the necessities of the location. The details of these 14, 1939. desks are described.
-
F
OR five y y s a course of chemical microscopy was given a t the University of Maine in the physical chemistry laboratory during mornings when this was not being used for its designed course. The tables in this laboratory were thirty-six inches high
that with a microscope set twenty-four inches from the wall a t a height of thirty-six inches the mirror could not reflect light from the sky into the microscope without the edge of the stage or the bottom of the window occupying part of the field of view. The table height of twenty-seven inches recommended bv Chamot2 and Cools would, of course, be still worse. it was decided, therefore, to raise the top of the table almost to the level of the bottom of the window, to raise the height of the chair seat the same amount and to include a resting place for the feet twenty-seven inches below the table top. The accompanying sketch shows the design of the working space for one student. Pour of these tables
USINGTHE MICROSCOPE WHILESTANDING
with the usual straight front. The positions required for observation through a microscope were most uncomfortable. The straight front obliged a Derson sitting on a stool to spreid his knees Far ap& or to sit sideways so that he might get close to the microscope. When standing the average person had to stoop to get his eye a t the .eye-point of the ocular, and this was tiring. I n addition only half the natural light was furnished by.a north window, the other by an east window with ils consequent glare in ther&rnings. And the sills of these windows were so high that the whole field of a microscope placed directly in front of a window conld not be illuminated. The other laboratory tables were so situated that their use was impossible. As in most chemical laboratories, there were no unused rooms in the building, and search was made for suitable space that could be used without interfering too much with its primary purpose. The selected location was the rear of a recitation room. Portunately, this was a north wall and had two windows in its twenty-three feet. By removing the last row of chairs, tables suitable for microscopy conld be installed if they were placed parallel to the wall. This change would, of course, reduce the capacity of the room for recitations, but it was rarely used to full capacity for this purpose. The microscopy laboratory could be 'scheduled for afternoons, while the room was used for recitations only in the mornings. The bottoms of the windows were forty-five inches from the floor and the previous experience had shown
I
CSING ,THE A I I C R O S C O F\Ywrr,i; ~ SEATED ON HIGHSTOOL ,
were built by a local concern and together with an alberene sink occupied the available wall length of twenty-three feet. As recommended by Chamot a semi-oval section (twenty-two inches wide and eight inches deep in the middle) was cut out of the table top to enable the student to rest his elbows on the desk while using the microscope and also to p i w t somewhat to work with different apparatus. This was placed a little to the left of the center in order to make the drawers on the right as large as possible while still leaving room for the microscope case in the cupboard on the left. The cupboard was placed on the left and the drawers on the right because a student has to reach many times in a laboratory period for various small pieces of apparatus, but usually only once for his microscope. This also allows more desk-top space for work
CHAMOT, "Laboratory construction and equipment," National Research Council Committee Report, The Chemical Foundation. Inc.. New York Citv. 1930. o. 235. 3 COOL,"A small 1ahoratory.for chekical microscopy," J. CAEM.EDUC.,9, 2084-9 (1932).
'
with his right than with his left hand. The four top drawers are assigned separately to students in different laboratory sections who use the microscope cupboard in common. The large drawers a t the bottom, being unhandy for the student to use while seated and also
An unexpected result was the ease of working while standing up a t the desk. The fortyone inch height brings notebook, burner, reagent block, microscope, and other equipment to a more comfortable position for observation than the usnal thirty-six inch desk. Even relatively short students iind this comfortable. Thus,
- -
.. . - - .. .
~r---------i
i
I I
Scale: I.= 1 '
drip
areore
VIEWOX. MICROSCOPY TABLES AT REAROF RECITATION ROOM
not needed for this purpose, are used by the instructor for storage of special equipment. Setting the center drawer back eight inches allows the stool to be pulled up into the opening so that the student may sit corn: fortably while taking advantage of the "cut-out" place. Large pieces of equipment, such as a micro-. balance, euscope and comparison microscope, are stored in a cupboard in the lecture table in the room. The stools, which are of a standard commercial pattern, are adjustable to a height of thirty-three inches. Sitting on the stool with his feet in the space above the center drawer, the student is in the same position as if he were on a chair of ordinary height a t a desk twenty-seven inches high. The same result would have been attained by building a platform fourteen inches high, but this would have had'to extend about three feet in front of the desk to allow for the stool being pushed back and would have taken additional space from the room for recitation purposes. There would also have been some danger of accidents.
k
ELEVATION
I ekw out
..
+Q
fwd. See plan
MICROSCOPY TABLE
the student has two possible positions which he can assume alternatively as he wishes. , :, The tables have been in use now for three years and have been found entirely satisfactory. This experience shows how little space is needed for a microscopy laboratory and how it may be found in a crowded chemistry building.
