382 PHILOSOPHICAL TRANSACTIONS. [aNNO \66q, 



VI. Abrege Chronologique de THistoire Sacree et Prophane, par le P. 

 Labbe, de la Comp. de Jesus. Paris, in 12mo. in 5 volumes. 



Extract of a Letter containing the ivhole Process used in France for 

 making Sea Salt hy the Sun. Communicated to the Editor hy a 

 French Physician, residing near tJie chief Place where it is practised. 

 N'^dh p. 1025. 



Sir, — I send you the plan of our salt marishes, with the way of making our 

 salt. 



AAA, is the sea. (Fig. 6, pi. g.)— 1 1, the entry, by which the sea- water 

 passes into B B. — B B, the first receptacle ; in which the water is kept 20 

 inches deep. — CCC, the second receptacle, where the water makes three 

 turnings, as you see, and is 10 inches deep. — 22, the opening, by which the 

 first and second receptacle have communication one with another. — E E F, the 

 third receptacle, which is properly called the marish. — dddddd, is a channel 

 very narrow, through which the water must pass before it passes out of the se- 

 cond receptacle into the third. — 33, is the opening, by which the water runs 

 out of the second into the third receptacle. The pricks, you see in the water 

 throughout the whole scheme, mark the course and turnings, which the water 

 is forced to make before it comes to h h h h h, which are the places where the 

 salt is made. — h hhhh, are the beds of the marish, where the salt is made ; and 

 in them the water must not be above an inch and a half deep. Each of these 

 beds is 15 feet long and 14 feet broad. 



99999, are the little channels between the beds. 



88888, are the apertures, by which the beds receive the sea-water after 

 many windings and turnings. 



When it rains, the openings 22, 33, are stopped, to hinder the water from 

 running into the marish marks, E E F. Unless it rain much, the rain-water 

 does little hurt to the marish ; and although it rain a day or a night, we do 

 not let the water which is in the marish run out, the heat of tl^e sun suffici- 

 ently exhaling such rain-water, if for example it be not above an inch high. 

 Only, if it have rained very plentifully that day, no salt is drawn for the three or 

 four next following days. But if it rain five or six days, the people are then 

 forced to empty all the water of the beds by a peculiar channel, conveying it 

 into the sea ; which channel cannot be opened, but when it is low water. But 

 it very seldom rains so long as to constrain men to empty those beds. 



It is obvious, that in the hottest years most salt js made, and besides the heat 

 of the sun, the winds contribute much to it, as less salt is made in calm than 

 in windy weather. The west and north-west winds are the best for this purpose. 



